- Mathematical Definition
- Thirty is an even composite number composed of the prime factors two, three, and five.
My sister recently celebrated her thirty birthday with a large party.
- Timekeeping Usage
- It is used to indicate the halfway point of an hour, often referred to as half past.
The speed limit in this residential area is strictly thirty miles per hour.
The current score in the tennis match is fifteen to thirty.
- Financial Context
- It frequently appears in pricing, discounts, and mortgage terms, such as a thirty-year fixed-rate mortgage.
We have exactly thirty days left to finish this comprehensive project.
There were over thirty people waiting in line outside the popular bakery this morning.
The teacher handed out thirty assignments to the students in the classroom.
- Plural Noun Agreement
- Because thirty represents a quantity greater than one, the noun it modifies must always be in its plural form.
My father is thirty-five years old today.
- Time Expressions
- In digital time reading, you state the hour followed directly by thirty, such as seven thirty.
The train is scheduled to depart the station at exactly four thirty in the afternoon.
Jazz music was incredibly popular throughout the nineteen thirtys.
- Age References
- You can use the phrase 'in his thirties' or 'in her thirties' to describe someone whose age is between thirty and thirty-nine.
We will take a short thirty-minute intermission before the second act begins.
That beautiful winter coat is on sale for only thirty euros.
- Retail Environments
- Prices, discounts, and return policies frequently utilize this number, such as a thirty-day money-back guarantee.
The next train to London will depart from platform four in thirty minutes.
- Workplace Scheduling
- Calendar invitations and meeting durations are heavily reliant on thirty-minute intervals.
The quarterback was tackled aggressively right on the thirty-yard line.
- Social Milestones
- The transition from one's twenties to their thirties is a popular topic in media, literature, and everyday conversation.
She felt a sudden wave of anxiety as her thirtyth birthday rapidly approached.
The meteorologist predicts that temperatures will soar above thirty degrees Celsius tomorrow afternoon.
- Pronunciation Stress
- In thirty, the stress falls heavily on the first syllable (THIR-ty), whereas in thirteen, the stress falls on the second syllable (thir-TEEN).
Make sure you pay exactly thirty dollars, not thirteen dollars, for the admission ticket.
- Spelling Errors
- It is essential to memorize the specific sequence of letters: t-h-i-r-t-y, noting the absence of an 'e' before the 'y'.
The student misspelled the word thirty on his final mathematics examination.
He signed a comprehensive thirty-year mortgage for his new house.
- Compound Adjectives
- When a number and a noun form a compound adjective before another noun, the included noun remains singular.
Practicing the pronunciation of thirty helped her improve her overall English accent.
The recipe calls for exactly thirty grams of fine caster sugar.
- Dozen Multiples
- Sometimes, quantities close to thirty are expressed using dozens, such as 'two and a half dozen', which exactly equals thirty.
The baker prepared two and a half dozen cookies, which equals exactly thirty cookies.
- Time Alternatives
- Instead of saying 'six thirty', you can say 'half past six' to convey the exact same meaning regarding the time of day.
The meeting is scheduled to begin at half past two, or two thirty.
The new manager is a highly energetic thirty-something professional with great ideas.
- Approximations
- Words like 'approximately', 'nearly', and 'almost' are frequently paired with thirty to give an estimate rather than an exact count.
We expect approximately thirty guests to attend the charity dinner tonight.
He spent nearly thirty years working diligently in the same factory.
Examples by Level
I am thirty years old.
State your age using the verb 'to be'.
Use the verb 'am' with 'I' and the plural noun 'years'.
The time is ten thirty.
Expressing time digitally.
When reading digital time, state the hour then the minutes directly.
This book costs thirty dollars.
Stating the price of an item.
Use the plural noun 'dollars' after the number thirty.
There are thirty students in my class.
Stating the quantity of people in a room.
Use 'There are' for plural nouns like 'students'.
I have thirty apples in the basket.
Counting physical objects.
The noun 'apples' must be in its plural form.
My house is number thirty.
Giving a street address.
Numbers used as identifiers do not make the preceding noun plural.
Please open your book to page thirty.
Following classroom instructions.
When referring to a specific page, the number follows the noun.
We wait for thirty minutes.
Expressing a duration of time.
Use the preposition 'for' to indicate duration.
My mother is thirty-five years old.
Using compound numbers for age.
Use a hyphen when writing compound numbers like thirty-five.
The train arrives in thirty minutes.
Talking about future schedules.
Use the preposition 'in' to mean 'after a period of'.
September has exactly thirty days.
Stating facts about the calendar.
The verb 'has' agrees with the singular subject 'September'.
I bought thirty eggs at the supermarket.
Purchasing quantities of groceries.
Ensure the noun 'eggs' is pluralized correctly.
The speed limit here is thirty.
Discussing driving rules.
The noun 'miles per hour' is often implied and omitted.
She needs thirty more points to win the game.
Discussing scores in a game.
Use 'more' after the number to indicate an additional required amount.
There is a thirty percent discount on these shoes.
Talking about shopping sales.
The word 'percent' remains singular even after a plural number.
I usually wake up at six thirty in the morning.
Describing daily routines.
Use the preposition 'at' before specific times.
He is in his early thirties and works as an engineer.
Describing an approximate age range.
Use the plural 'thirties' with a possessive pronoun to indicate an age decade.
We have a thirty-minute break for lunch today.
Using numbers as compound adjectives.
When used as an adjective, 'thirty-minute' is hyphenated and singular.
The temperature reached thirty degrees Celsius yesterday.
Discussing weather and temperature.
The noun 'degrees' must be pluralized.
I have been waiting here for almost thirty minutes.
Expressing frustration over duration.
Use 'almost' to indicate a number slightly less than thirty.
My grandparents were born in the nineteen thirties.
Referring to a historical decade.
Decades are pluralized, often written with an 's'.
The recipe requires exactly thirty grams of butter.
Following precise cooking measurements.
Measurements require the plural form of the unit, like 'grams'.
She has visited over thirty different countries in her life.
Expressing a large quantity of experiences.
Use 'over' to mean 'more than' a specific number.
The tennis player is currently leading thirty to fifteen.
Announcing a sports score.
In scores, the numbers are stated sequentially.
The bank offered them a thirty-year fixed-rate mortgage.
Discussing complex financial products.
Example
There are thirty days in November.
Related Content
Learn it in Context
This Word in Other Languages
Related Phrases
More general words
a lot of
A2A large amount or number of; plenty of.
about
A1On the subject of; concerning something.
above
A2In a higher place than something or someone.
accident
A2An unfortunate event causing damage or injury.
action
A2The process of doing something, typically to achieve an aim.
after
A2Following in time or place; later than.
afterward
A2At a later or subsequent time.
again
A2Another time; once more.
aged
B1Of a specified age.
alive
A2Living, not dead.