用你的语言查看此页面

English

فارسی

العربية

Deutsch

Español

Français

日本語

한국어

Português

हिन्दी

首页
学习
英语
词汇
emission

B2 adjective #24 最常用 12分钟阅读

emission

前24

At the A1 level, you can think of 'emission' as a special word for smoke or gas that comes out of something, like a car or a big factory. Imagine you are walking down the street and you see a car with a lot of black smoke coming from the back. That smoke is an emission. You don't need to use this word often at A1, but you might see it on signs or in simple books about the earth. It just means something is being sent out. For example, 'The car has bad emissions' means the car is making the air dirty. It is a formal way to talk about things that come out into the air. You can remember it by thinking of the letter 'E' for 'Exit'. The gas is exiting the car. In simple English, we usually say 'smoke' or 'gas', but 'emission' is the 'grown-up' word for it. When you learn about science in school, this is one of the first big words you will hear. It helps you talk about why the air is sometimes not clean. Even though it is a long word, its meaning is very simple: things going out into the world.

For A2 learners, 'emission' is an important word for talking about the environment and cars. You will often see it used as an adjective to describe tests or rules. For example, an 'emission test' is a check for your car to see if it is too dirty for the air. Many cities have 'low emission zones' where only clean cars can drive. At this level, you should know that emissions are usually gases like carbon dioxide that are not good for the planet if there are too many of them. You might hear people say, 'We need to stop carbon emissions.' This means we need to stop putting bad gas into the air. It is a noun, but we use it like a describing word in phrases like 'emission levels' or 'emission standards'. When you write about your city or about nature, using this word makes your English sound more serious and correct. It is better than just saying 'dirty air'. Remember that it usually refers to things you can't always see, like heat or invisible gases, not just big clouds of black smoke.

At the B1 level, you should be comfortable using 'emission' in discussions about climate change and technology. You will notice that it is often used in the plural form, 'emissions', when talking about the total amount of pollution from a country or a company. For example, 'The United Kingdom is trying to reduce its greenhouse gas emissions.' You should also understand its use in science, such as the 'emission of light' from a lamp or the 'emission of heat' from a fire. This word is very common in news articles and documentaries. You might also encounter it in more specific phrases like 'zero-emission vehicles' (cars that don't produce any pollution) or 'emission trading' (a way for companies to buy and sell the right to pollute). Using 'emission' correctly shows that you can handle technical topics. It is a more precise word than 'release' or 'discharge' when you are talking about the atmosphere. You should also be careful not to confuse it with 'omission', which means leaving something out. Emission is about sending something out into the environment.

At the B2 level, 'emission' is a key term for academic and professional communication. You are expected to understand its various nuances, such as the difference between 'point source emissions' (from a single pipe) and 'diffuse emissions' (from many small sources). You should be able to use it as an attributive noun (acting as an adjective) in complex phrases like 'emission mitigation strategies' or 'emission intensity'. At this level, you should also be aware of its scientific applications beyond pollution, such as 'spontaneous emission' in physics or 'acoustic emission' in engineering. The word carries a formal tone and is essential for writing essays on environmental policy, sustainability, or industrial processes. You should also be familiar with the collocations that go with it, such as 'curtail emissions', 'offset emissions', or 'monitor emission levels'. Understanding the socio-economic context of 'emission credits' and 'carbon emission taxes' is also important for B2 learners who are interested in current affairs. Your ability to use this word accurately in both singular and plural forms will demonstrate a high level of lexical resource.

For C1 learners, 'emission' is a versatile tool for precise technical and philosophical expression. You should be able to discuss the 'emission spectra' of chemical elements and how they are used in spectroscopy to identify substances. In a medical or biological context, you might use it to describe the 'emission of neuro-transmitters' or other physiological discharges. At this level, the word is not just about pollution; it is about the fundamental physical act of radiation and discharge. You should be able to integrate it into complex sentence structures, such as 'The anthropogenic emission of greenhouse gases has reached a critical threshold, necessitating immediate systemic intervention.' You should also understand the subtle differences between 'emission', 'effluence', and 'exhalation', choosing the most appropriate term for the register and domain. C1 learners should also be comfortable with the word's use in figurative or highly specialized contexts, such as the 'emission of a new currency' in older economic texts, though this is now rare. Your mastery of this word should include a deep understanding of its Latin roots and how it relates to other words in the same family, like 'emissary' or 'emittance'.

At the C2 level, you possess a comprehensive and nuanced command of 'emission' across all possible domains. You can use it to discuss the intricacies of quantum mechanics, such as 'stimulated emission' which is the principle behind laser technology. You understand its role in complex international legal frameworks, such as the 'Emission Trading Scheme' (ETS) of the European Union, and can debate the ethical implications of 'emission outsourcing' where developed nations move their polluting industries to developing ones. Your usage should be flawless, reflecting an understanding of the word's countability, its role as a modifier, and its precise scientific definitions. You might use the word in high-level academic papers to describe the 'thermal emission profiles' of planetary bodies or the 'emission characteristics' of advanced nanomaterials. At this level, 'emission' is more than just a vocabulary word; it is a conceptual building block used to describe the flow of energy and matter in the universe. You are also capable of using the word in creative or literary contexts, perhaps metaphorically describing the 'emission of hope' from a desperate situation, though its primary strength remains in its technical and formal precision.

开始练习例句笔记与提示

emission 30秒了解

Emission is the process of releasing substances or energy, such as gases, light, or heat, from a source into the surrounding environment or atmosphere.
It is a central term in environmental science, used to describe pollution from cars and factories, and is often subject to strict legal regulations.
In physics and chemistry, it refers to the release of electromagnetic radiation, such as light, when an object or particle loses energy or changes state.
The word is frequently used as a modifier in phrases like 'emission standards' or 'emission testing' to specify the nature of a rule or procedure.

The term emission, when functioning in an adjectival or attributive capacity, describes anything related to the process of sending out, discharging, or releasing substances or energy into the surrounding environment. While traditionally categorized as a noun, its frequent use in compound structures—such as emission standards or emission testing—allows it to function as a descriptor for regulatory, scientific, and environmental contexts. At its core, the concept involves a transition from an internal state to an external one, whether that be gas leaving an exhaust pipe, light radiating from a star, or heat dissipating from a thermal vent. In the modern era, the word has become synonymous with environmental responsibility and the global effort to combat climate change.

Environmental Context: Refers to the release of pollutants like carbon dioxide, methane, and nitrous oxide from industrial and domestic sources.

The government implemented strict emission controls to improve urban air quality.

In scientific discourse, the word is used to describe the spectrum of light or radiation produced by an object. For instance, an emission spectrum is a unique fingerprint of colors that tells scientists exactly which elements are present in a distant galaxy. This technical application is vital in physics and chemistry, where the behavior of electrons jumping between energy levels results in the emission of photons. Understanding these patterns allows for advancements in medical imaging, telecommunications, and deep-space exploration.

Technical Context: Relates to the discharge of electromagnetic waves or particles from a source, such as a radio transmitter or a radioactive isotope.

Scientists studied the emission patterns of the newly discovered pulsar.

Beyond the physical sciences, the word appears in economic and policy discussions. Terms like emission trading or emission credits refer to market-based approaches to reducing pollution. Here, the word describes the legal and financial frameworks built around the right to release a certain amount of greenhouse gases. This shift from a purely physical description to a socio-economic one highlights how deeply the concept of discharge is woven into the fabric of modern civilization and its survival strategies.

The new emission tax aims to incentivize green energy adoption.

The versatility of the word allows it to be used in both microscopic and macroscopic scales. It can describe the microscopic emission of an alpha particle from an atom's nucleus or the macroscopic emission of volcanic ash during a massive eruption. In every case, the focus remains on the movement of something from the 'inside' to the 'outside'. This fundamental movement is what defines the word across all disciplines, making it a cornerstone of technical English vocabulary.

Regulatory Context: Involves the legal limits set by authorities on how much waste or gas a company can legally release.

The car failed its emission test due to a faulty catalytic converter.

Global emission levels must peak before 2025 to avoid climate catastrophe.

Using emission correctly requires an understanding of its role as a noun that frequently acts as a modifier. When you use it to describe a noun that follows, you are essentially creating a compound noun that functions like an adjective. For example, in the phrase emission reduction, the word 'emission' tells us exactly what kind of reduction we are talking about. This is a very common pattern in formal, scientific, and journalistic writing. It is important to distinguish between the singular 'emission' (referring to the general concept or a specific act) and the plural 'emissions' (referring to the actual substances being released).

Compound Noun Usage: The word is placed directly before another noun to specify the category of the second word.

The factory invested in new emission scrubbing technology.

In academic writing, you will often see the word paired with verbs like monitor, curtail, calculate, or offset. These combinations help describe the management of environmental impact. For instance, a company might 'offset its carbon emission' by planting trees. Notice how the word remains singular when it is part of a specific technical term like 'carbon emission' used as a singular concept, though 'carbon emissions' is also widely accepted and perhaps more common when referring to the total volume of gas.

Scientific Precision: Use the word to describe the specific type of energy being released, such as light or heat.

The emission of light from the LED is highly efficient.

When discussing vehicles, the word is almost always used in the context of testing and compliance. You might say, 'My car passed the emission check,' or 'The manufacturer was fined for cheating on emission data.' In these sentences, the word serves to specify that the check or the data is related to the gases coming out of the tailpipe. This usage is standard in both American and British English, making it a globally recognized term in the automotive industry.

Electric vehicles are often marketed as zero-emission transport options.

Finally, consider the word's use in the medical and biological fields. It can describe the release of substances from the body. While less common in everyday speech, you might encounter it in medical reports describing the 'emission of fluids' or 'semen emission'. In these contexts, the word maintains its formal, clinical tone. It is precise and avoids the potential vulgarity or ambiguity of more common words, which is why it is preferred in professional medical documentation.

Clinical Usage: Refers to the physiological release of substances from a biological organism.

The study tracked the emission of pheromones in honeybees.

The emission rate of the gas was measured in parts per million.

In the 21st century, you are most likely to hear the word emission during news broadcasts concerning the environment. Journalists frequently discuss 'net-zero emission' targets, which are goals set by countries to balance the amount of greenhouse gases produced with the amount removed from the atmosphere. This phrase has become a staple of political rhetoric and corporate social responsibility reports. If you listen to a speech by a world leader at a climate summit, the word will likely appear dozens of times as they debate the future of the planet's atmosphere.

News & Media: Used to describe national goals and international treaties regarding pollution levels.

The BBC reported on the record-breaking emission levels recorded last summer.

Another common place to encounter this word is at the mechanic or car dealership. When purchasing a new vehicle, the 'emission rating' is a key piece of information on the window sticker. It tells the buyer how much carbon dioxide the car produces per kilometer. Furthermore, in many regions, an 'emission test' is a legal requirement for renewing a vehicle's registration. You will hear mechanics say, 'Your car failed the emission test because of a leak in the exhaust manifold.' This practical, everyday usage makes the word essential for anyone who owns or operates a vehicle.

Automotive Industry: Refers to the testing and rating of vehicle exhaust systems to meet legal standards.

The city expanded its ultra-low emission zone to include the suburbs.

In the world of science and technology, specifically in physics documentaries or university lectures, the word is used to explain how light and energy work. You might hear a narrator say, 'The sun's energy emission sustains life on Earth.' Or in a chemistry lab, a professor might discuss the 'emission of heat' during an exothermic reaction. This usage is precise and technical, focusing on the laws of thermodynamics and the behavior of matter. It is a word that bridges the gap between the visible world (smoke) and the invisible world (radiation).

The telescope was designed to detect the infrared emission of distant stars.

Finally, you will find the word in legal and corporate documents. Companies often publish 'emission reports' to satisfy shareholders and regulators. These documents detail the company's environmental footprint and their plans for 'emission mitigation'. In this context, the word is part of a formal vocabulary used to manage risk and reputation. It is less about the physical act of release and more about the accountability and management of that release in a globalized economy.

Corporate & Legal: Relates to the reporting and management of environmental impact by large organizations.

The corporation faced a lawsuit for falsifying its annual emission data.

The emission of noise from the construction site was strictly regulated.

One of the most frequent errors learners make is confusing emission with omission. While they sound somewhat similar, their meanings are opposite. 'Emission' is about putting something out (sending it forth), whereas 'omission' is about leaving something out (failing to include it). For example, if you forget to include a fact in a report, that is an omission. If your car releases smoke, that is an emission. Mixing these up in a formal report can lead to significant confusion, especially in legal or scientific contexts where precision is paramount.

Emission vs. Omission: Emission = Sending out. Omission = Leaving out.

Incorrect: The omission of gas from the factory was dangerous. (Should be emission).

Another common mistake involves the countability of the word. Many learners use the singular 'emission' when they should use the plural 'emissions'. Generally, when referring to the total volume of pollutants produced by a country or an industry, the plural form is preferred: 'Global carbon emissions are rising.' The singular 'emission' is better suited for the act itself or when used as an adjective/modifier: 'The emission of light,' or 'An emission standard.' Using the singular form to describe global pollution can sound slightly unnatural to native speakers.

Singular vs. Plural: Use 'emissions' for substances/volumes and 'emission' for the process or as a modifier.

The company is working to lower its total greenhouse gas emissions.

Learners also sometimes confuse 'emission' with 'transmission'. While both involve movement, 'transmission' specifically refers to the movement of a signal, a disease, or power from one place to another (often through a medium). 'Emission' is simply the act of the source releasing the thing. For example, a radio tower emits waves, and the transmission of the signal allows you to hear the music. If you say 'the transmission of smoke,' it sounds like the smoke is being sent as a message, which is usually not what is intended.

Incorrect: The transmission of CO2 from cars is a problem. (Should be emission).

Finally, be careful with the word 'remission'. In a medical context, 'remission' means a period where symptoms of a disease disappear. This is entirely unrelated to 'emission'. If a patient says, 'My cancer is in emission,' they are accidentally saying their cancer is releasing something, rather than being under control. This is a critical distinction in healthcare communication. Always double-check the prefix: 'e-' for out, 're-' for back or again, and 'o-' (ob-) for against or away.

Emission vs. Remission: Emission = Release. Remission = Reduction/Disappearance of disease.

The patient was happy to hear that his illness was in remission.

The emission of sparks from the fire was a safety concern.

While emission is the most formal and technical term, there are several alternatives depending on the context. If you are talking about fluids or gases in a less formal way, release is a perfect substitute. 'Release' is broader and can apply to anything from a prisoner being set free to a new movie coming out, but in environmental terms, 'the release of gases' is very common. It lacks the scientific weight of 'emission' but is more accessible for general audiences.

Release vs. Emission: 'Release' is general and common; 'Emission' is technical and formal.

The release of chemicals into the river was accidental.

In the context of waste and liquid pollutants, discharge is often the preferred term. You will hear about a factory 'discharging' waste into a sewer system. 'Discharge' implies a more forceful or intentional act of getting rid of something. It is also used in medical contexts (e.g., 'ear discharge') and military contexts (e.g., 'discharging a weapon'). While 'emission' can cover these areas, 'discharge' is more specific to the act of emptying or clearing out a container or system.

Discharge vs. Emission: 'Discharge' is for liquids/waste; 'Emission' is for gases/radiation.

The battery's discharge rate determines how long the device will last.

When discussing energy or light specifically, radiation is a strong alternative. While 'emission' describes the act of the source sending the energy out, 'radiation' describes the energy itself as it travels through space. For example, 'The emission of heat from the radiator' focuses on the radiator, while 'The radiation of heat across the room' focuses on the heat moving through the air. In casual speech, 'radiation' often has a negative connotation (nuclear radiation), but in science, it is a neutral term for energy transport.

Solar radiation is the primary source of energy for the Earth.

Finally, consider exhalation or effluence. 'Exhalation' is specifically for breathing out, while 'effluence' is a very formal word for something that flows out, often used in environmental law to describe liquid waste. These words are much more niche than 'emission' but can provide variety in your writing if you are looking for a very specific nuance. For most B2 learners, mastering 'emission' and 'release' will cover 90% of all necessary situations.

Exhalation vs. Emission: 'Exhalation' is biological (breathing); 'Emission' is general/mechanical.

The exhalation of carbon dioxide is a natural part of the respiratory cycle.

The factory's effluence was monitored by the environmental agency.

How Formal Is It?

正式

中性

非正式

Child friendly

俚语

趣味小知识

The word 'emissary' comes from the same root; an emissary is a person 'sent out' on a special mission.

发音指南

UK /ɪˈmɪʃ.ən/

US /iˈmɪʃ.ən/

The stress is on the second syllable: i-MIS-sion.

押韵词

commission permission submission transition condition position ambition addition

常见错误

Pronouncing the first 'e' as a strong 'A' (e.g., ay-mission).
Confusing the 'sh' sound with a 'zh' sound.
Putting the stress on the first syllable (E-mission).
Failing to pronounce the 'n' clearly at the end.
Mixing it up with 'omission' by starting with an 'o' sound.

难度评级

阅读 4/5

Common in news and science articles, but requires context to distinguish between light and pollution.

写作 5/5

Requires careful use of singular vs plural and correct collocation with verbs like 'curtail' or 'offset'.

口语 3/5

Easy to pronounce once the stress is learned, but mostly used in formal discussions.

听力 4/5

Can be confused with 'omission' or 'remission' if the speaker is fast.

接下来学什么

前置知识

gas smoke release factory environment

接下来学习

mitigation sustainability anthropogenic sequestration thermodynamics

高级

spectroscopy emissivity effluence photovoltaic isotope

需要掌握的语法

Attributive Nouns

In 'emission standards', 'emission' is a noun acting like an adjective to describe 'standards'.

Countability in Environmental Contexts

Use 'emissions' (plural) when referring to the total quantity of pollutants: 'The country's emissions are high.'

Prepositional Phrases

Use 'of' to connect the act to the substance: 'The emission of methane'.

Zero-Derivation (Verb to Noun)

The word comes from the verb 'emit', but 'emission' is the standard noun form for the result.

Compound Adjectives

Use a hyphen for compound adjectives like 'zero-emission' when they come before a noun.

按水平分级的例句

The car has a lot of smoke emission.

The car is sending out a lot of smoke.

Here 'emission' is a noun used to describe the smoke.

We see the emission from the big factory.

We see the stuff coming out of the factory.

Used with 'the' to show a specific thing.

Is the emission from the fire dangerous?

Is the smoke from the fire bad?

A question about the substance being released.

The bus has very low emission.

The bus is clean and does not make much smoke.

Used as a singular noun here.

I saw a bright light emission.

I saw a flash of light.

Describes the act of light coming out.

The car failed the emission test.

The car did not pass the smoke check.

Used as an adjective to describe 'test'.

Stop the gas emission now.

Stop the gas from coming out.

An imperative sentence using 'emission'.

Plants help with oxygen emission.

Plants give out oxygen.

Describes a natural process.

Many cities have a low emission zone.

A place where only clean cars can go.

Used as an adjective to describe 'zone'.

We must reduce the emission of carbon.

We must make less carbon gas.

The 'emission of [substance]' pattern.

The new heater has zero emission.

The heater is very clean.

Compound adjective 'zero-emission'.

The scientist measured the light emission.

The scientist checked the light.

Noun phrase 'light emission'.

The factory's emission is monitored daily.

People check the factory's smoke every day.

Possessive 'factory's' followed by 'emission'.

Electric cars have no tailpipe emission.

Electric cars don't have smoke from the back.

Specifying the type of emission.

Volcanoes have natural gas emission.

Volcanoes send out gas naturally.

Using 'natural' to describe the emission.

The emission levels are too high today.

There is too much pollution today.

Plural-like usage with 'levels'.

The government is setting new emission standards.

The government is making new rules for pollution.

Attributive noun usage.

We need to lower our greenhouse gas emissions.

We need to produce less bad gas for the planet.

Plural 'emissions' for total volume.

The car's emission control system is broken.

The part that cleans the car's smoke is not working.

Complex compound noun.

The emission of methane is a major problem.

Releasing methane gas is a big issue.

Formal 'the emission of' structure.

They are studying the heat emission of the building.

They are looking at how much heat the building loses.

Scientific application.

The company was fined for illegal emission.

The company had to pay money for polluting.

Legal context.

Solar panels have no operational emission.

Solar panels don't pollute when they work.

Technical descriptor.

The emission spectrum helps identify the gas.

The light pattern shows what the gas is.

Specific scientific term.

The treaty aims to cap global carbon emissions.

The agreement wants to limit the world's carbon.

Using 'cap' as a verb with 'emissions'.

The factory installed an emission scrubbing unit.

The factory put in a machine to clean the air.

Highly technical compound noun.

The emission intensity of the industry has decreased.

The amount of pollution per product is lower.

Economic/Environmental term.

Radioactive emission can be dangerous to humans.

Radiation from nuclear things can hurt people.

Physics context.

The car manufacturer manipulated the emission data.

The car company changed the pollution numbers.

Journalistic/Legal context.

The spontaneous emission of photons was observed.

They saw light particles being released naturally.

Advanced physics usage.

We are looking for ways to offset our emission.

We want to balance our pollution by doing good things.

Sustainability context.

The city's emission profile is mostly from transport.

Most of the city's pollution comes from cars and buses.

Analytical usage.

The policy focuses on the mitigation of fugitive emissions.

The rule is about stopping accidental gas leaks.

Technical term 'fugitive emissions'.

The star's emission lines were shifted toward the red.

The light from the star looked more red than usual.

Astronomy context (Redshift).

The emission of volatile organic compounds must be curtailed.

We must stop releasing certain chemicals.

Formal scientific nomenclature.

The report analyzes the lifecycle emission of the product.

The report looks at pollution from start to finish.

Environmental auditing term.

The acoustic emission from the bridge indicated a crack.

The sound coming from the bridge showed it was breaking.

Engineering context.

The country is a net-zero emission pioneer.

The country is a leader in balancing its pollution.

Political/Economic praise.

The emission of pheromones triggers a social response.

Releasing chemicals makes the group act together.

Biological context.

The thermal emission was captured by the satellite.

The satellite saw the heat coming off the ground.

Remote sensing context.

The stimulated emission of radiation is the basis for lasers.

Forcing light out is how lasers work.

Fundamental physics definition.

The philosophical implications of carbon emission are profound.

The meaning of our pollution for the future is deep.

Abstract/Philosophical usage.

The treaty addresses the transboundary emission of pollutants.

The agreement is about pollution that crosses borders.

International law terminology.

The emission characteristics of the plasma were anomalous.

The way the plasma released energy was strange.

High-level scientific observation.

The project aims to decouple economic growth from emission.

The goal is to grow the economy without more pollution.

Macroeconomic theory.

The secondary emission of electrons was measured precisely.

They checked the extra electrons being knocked out.

Particle physics context.

The emission of a new decree caused widespread unrest.

Sending out a new law made people angry.

Archaic/Formal usage for 'issuing'.

The anthropogenic emission signature is clearly visible in the ice cores.

The human-made pollution mark is in the old ice.

Paleoclimatology context.

近义词

discharge release exhalation effluence radiation outflow

反义词

absorption intake containment

常见搭配

carbon emission

emission standards

zero emission

emission spectrum

greenhouse gas emissions

emission reduction

light emission

emission test

toxic emission

spontaneous emission

常用短语

net-zero emissions

low-emission zone

emission trading scheme

tailpipe emissions

fugitive emissions

emission-free

carbon emission tax

point source emission

emission monitoring

direct emissions

容易混淆的词

emission vs omission

Omission means leaving something out. Emission means sending something out.

emission vs transmission

Transmission is sending a signal or power through something. Emission is the initial release from the source.

emission vs remission

Remission is a medical term for a disease going away. It is not related to releasing substances.

习语与表达

"emission-free future"

A hopeful vision of a world where human activity does not pollute the air.

Scientists are working hard to build an emission-free future.

journalistic

"cut emissions to the bone"

To reduce pollution to the absolute minimum level possible.

The new law requires factories to cut emissions to the bone.

informal/metaphorical

"emission footprint"

The total amount of greenhouse gases produced by a person or organization.

Traveling by train instead of plane reduces your emission footprint.

common

"emission ceiling"

The maximum legal limit for the amount of pollution allowed.

The government lowered the emission ceiling for the shipping industry.

formal/legal

"emission gap"

The difference between current pollution levels and what is needed for safety.

The report highlighted a dangerous emission gap in global policy.

academic/political

"zero-emission target"

A specific goal to eliminate all harmful releases by a certain date.

The company's zero-emission target is very ambitious.

business

"emission spike"

A sudden and sharp increase in the amount of substance released.

The cold winter led to an emission spike from home heating.

news

"offsetting emissions"

Doing something good for the environment to cancel out the harm of pollution.

Planting trees is a popular way of offsetting emissions.

common

"emission intensity"

The amount of pollution produced per unit of economic output.

The country has successfully lowered its emission intensity.

economic

"emission scrubbing"

The process of removing pollutants from exhaust gases before they are released.

Emission scrubbing is expensive but necessary for coal plants.

technical

容易混淆

emission vs effluence

Both refer to things coming out of a source.

Effluence is specifically liquid waste flowing into water. Emission is usually gas or energy into the air.

The factory's effluence polluted the river, while its emissions polluted the air.

emission vs exhaust

Both describe gases from an engine.

Exhaust is the physical gas itself or the pipe. Emission is the act of releasing it or the measured amount.

The exhaust pipe was rusty, leading to higher carbon emissions.

emission vs radiation

Both involve energy leaving a source.

Emission is the act of the source sending it out. Radiation is the energy as it travels.

The emission of light from the sun results in solar radiation reaching Earth.

emission vs secretion

Both involve substances leaving a body or cell.

Secretion is a biological process for a specific purpose (like hormones). Emission is more general or mechanical.

The emission of sweat helps cool the body, but the secretion of adrenaline prepares it for action.

emission vs discharge

Both mean releasing something.

Discharge often implies emptying a container or a forceful release of waste/electricity. Emission is more about a continuous process.

The sudden discharge of the battery was unexpected, unlike the steady emission of heat.

句型

The [source] has [adjective] emission.

The car has bad emission.

We must reduce the emission of [substance].

We must reduce the emission of carbon dioxide.

[Source] failed the [type] emission test.

The factory failed the annual emission test.

[Country/Company] aims for net-zero emissions by [year].

The company aims for net-zero emissions by 2040.

The [device] is a [adjective]-emission model.

The heater is a low-emission model.

The emission of [substance] is a byproduct of [process].

The emission of sulfur is a byproduct of coal burning.

The [scientific tool] detects the [type] emission of [object].

The sensor detects the thermal emission of the engine.

The [adjective] emission signature suggests [conclusion].

The anomalous emission signature suggests a chemical leak.

词族

名词

动词

形容词

如何使用

frequency

Very common in news, science, and environmental policy.

常见错误

Using 'omission' instead of 'emission'. → The factory's emission was toxic.
Omission means leaving something out; emission means sending something out.
Saying 'emissions test' instead of 'emission test'. → I need an emission test for my car.
When used as a modifier before a noun, the singular form is more standard.
Pronouncing it as 'E-mission' (stress on first syllable). → i-MIS-sion
The stress must be on the second syllable for correct English pronunciation.
Using 'emission' for liquids in a casual way. → The pipe is leaking water.
While technically possible, 'leak' or 'discharge' is much more natural for liquids.
Forgetting the 's' when talking about global pollution. → Global emissions are rising.
When referring to total volumes of pollutants, the plural form is required.

小贴士

Singular vs. Plural

If you are writing about global warming, use 'emissions'. If you are writing about a car part, use 'emission'.

Use 'Emit' as the Verb

The verb form is 'emit'. Instead of saying 'The car makes an emission', say 'The car emits smoke'.

Environmental Focus

In 90% of modern news articles, 'emission' will refer to carbon dioxide and climate change.

Stress the Middle

Remember to say i-MIS-sion. The middle part is the loudest and longest part of the word.

Double 'S'

Don't forget the double 's' in the middle. It follows the pattern of 'mission' and 'permission'.

Sound More Academic

Replace 'smoke' with 'emissions' in your essays to get a higher score for formal vocabulary.

Specify the Type

Always try to say what kind of emission it is, like 'carbon emission', 'light emission', or 'noise emission'.

The 'E' Rule

E is for Exit. Emission is stuff exiting. O is for Out. Omission is stuff left out.

Car Checks

If your car's 'check engine' light is on, it might fail its next emission test.

Light and Heat

In a physics lab, use 'emission' to describe how energy leaves an atom.

记住它

记忆技巧

Think of the 'E' in 'Emission' as standing for 'Exit'. Emission is when something exits a source and goes into the world.

视觉联想

Imagine a car's exhaust pipe with a big green 'EXIT' sign over it, showing the gases leaving the car.

Word Web

Pollution Gas Light Heat Release Factory Exhaust Environment

挑战

Try to use 'emission' three times today: once about a car, once about a light, and once about a factory.

词源

Derived from the Latin word 'emittere', which is composed of 'ex-' (meaning 'out') and 'mittere' (meaning 'to send'). It literally means 'to send out'.

原始含义： The act of sending forth or discharging.

Indo-European (Latin branch)

文化背景

Be careful when discussing a country's emissions, as it can be a sensitive political topic regarding economic development.

In the US and UK, 'emission' is a standard term in school science curricula and daily news.

The 'Volkswagen Emission Scandal' (Dieselgate) is a famous modern reference. The 'Kyoto Protocol' was the first major international treaty focused on emissions. NASA's 'Earth Observatory' frequently publishes maps of global methane emissions.

在生活中练习

真实语境

Automotive Repair

Emission control system
Failed emission test
Check engine light
Exhaust manifold

Climate Change Debate

Net-zero emissions
Carbon footprint
Greenhouse effect
Renewable energy

Physics Laboratory

Emission spectrum
Photon release
Energy levels
Wavelength

Government Policy

Emission standards
Pollution tax
Regulatory compliance
Public health

Astronomy

Radio emission
Stellar radiation
Infrared detection
Cosmic background

对话开场白

"Do you think the new low-emission zones in cities are actually helping the air quality?"

"Has your car ever failed an emission test? What was the problem?"

"What are some simple ways we can reduce our daily carbon emission at home?"

"Should governments tax companies more based on their total annual emissions?"

"Are you interested in buying a zero-emission vehicle in the next few years?"

日记主题

Reflect on how your daily choices contribute to carbon emissions and what one change you could make to reduce them.

Describe a time you saw a significant emission of smoke or light. What was the source and how did it make you feel?

Write an argument for or against the implementation of a strict emission tax on all international flights.

Imagine a future where all transport is emission-free. How would our cities look and sound different than they do today?

Research the emission spectrum of a specific element and explain how it is used in modern technology.

常见问题

10 个问题

Grammatically, 'emission' is a noun. However, it is very frequently used as an attributive noun, which means it acts like an adjective to describe another noun, such as in 'emission standards' or 'emission test'.

Use the plural 'emissions' when you are talking about the total amount of pollutants or substances released by a country, industry, or vehicle. Use the singular 'emission' when talking about the process in general or using it as a modifier.

Yes, in physics, 'emission' is the standard word for the release of light or other electromagnetic radiation. For example, 'The emission of light from a laser is very precise.'

A zero-emission vehicle is one that does not release any pollutants from its onboard source of power. Electric cars are the most common example because they have no tailpipe emissions.

No. While it is often used for pollution, it can also describe natural and good things, like the emission of light from the sun or the emission of oxygen from plants.

It means that any greenhouse gases released into the atmosphere are balanced by an equal amount being removed, resulting in no net increase in the total amount of gases.

To pass an emission test, your car's exhaust system must be working correctly, and the engine must be burning fuel efficiently so that the pollutants are within legal limits.

It is a pattern of light produced by an element when it is heated. Each element has a unique emission spectrum, which scientists use like a fingerprint to identify it.

Not exactly. Smoke is a visible type of emission, but many emissions are invisible gases like carbon dioxide or methane, or energy like heat and light.

In medicine, it is used as a formal and clinical way to describe the release of bodily fluids or substances, such as 'semen emission' or the 'emission of pheromones'.