Grammar Rule in 30 Seconds
The Zero Conditional describes things that are always true, like scientific facts or personal habits, using the Present Simple in both clauses.
- Use Present Simple for the condition: 'If you heat ice...'
- Use Present Simple for the result: '...it melts.'
- Use a comma only if the 'if' clause comes first.
Overview
Zero Conditional の動きなんだ！これは絶対的な確実性と論理の文法だよ。「もし〜だったらいいな」とか「〜かもしれない」っていう話じゃなくて、always（いつも）起こることについて話すんだ。英文法の「科学の法則」だと思っていいよ。推測なしで、世界をありのままに説明するために使うんだ。物理の話でも、朝のコーヒーのルーティンの話でも、このパターンは最高の味方になるよ。シンプルで信頼性が高くて、日常会話で驚くほど強力なんだ。論理的なプロっぽく聞こえたいなら、このルールが必要だよ。How This Grammar Works
Zero Conditional はすべて原因と結果についてなんだ。切っても切れない2つの出来事を結びつけるんだよ。最初のことが起こる（条件）と、次のことが続く（結果）。お気に入りの店の「1つ買うと1つ無料（Buy One, Get One）」みたいなものさ。条件なしで結果は得られないからね。他の条件文とは違って、ここには「たぶん」はないんだ。100%保証だよ。文の両方の部分で Present Simple 時制を使うんだ。これで全てが「今」や「いつも」にしっかりと根付くことになる。地点Aから地点Bへの直線だと考えればいいよ。「登録」をクリックすれば、メールが届く。シンプルでしょ？結果について決して嘘をつかないから、最も正直な文法ルールなんだ。歯にほうれん草が挟まってたら必ず教えてくれる友達みたいにね。
Formation Pattern
if か when という単語で始める。
Present Simple を使って条件を加える。
if で始めた場合はカンマを置く。
Present Simple を使う。
if が真ん中に来るなら、カンマは要らないんだ。リバーシブルのジャケットみたいなものだね。どっちでも機能するし、いい感じだよ！
When To Use It
Zero Conditional が活躍する大きな瞬間が3つあるよ。- Scientific Facts: これらは普遍的な真理だ。赤と青を混ぜれば、紫になる。日が沈めば、暗くなる。重力に休みはないからね！
- Personal Habits: いつもやることについて使うよ。寝坊したら、朝食を抜く。犬を見かけたら、微笑む。君独自の「プログラミング」を説明するんだ。
- Rules and Instructions: テクニックのヒントやゲームのルールに最適だ。このボタンを押せば、ゲームがセーブされる。間違ったパスワードを入力すれば、アカウントがロックされる。
- Modern Scenarios: 午後6時にTikTokを投稿すれば、もっと見られる。VPNを使えば、データを守れる。インターネットでさえ、このルールに従うんだ！
Common Mistakes
- Using 'will' in the result: これが最大の間違いだ。みんなよく 'If I am tired, I will go to bed.' と言っちゃうけど、これは
First Conditionalなんだ。一般的な真理なら、こう言おう： 'If I am tired, I go to bed.' - Forgetting the comma:
ifで文が始まるなら、カンマは必須だよ。忘れると、息継ぎなしで長く走ってるみたいな文になっちゃう。 - Wrong tense:
Present Simpleにこだわって。一般的な真理にPresent Continuousは使わないで。 'If it rains, the grass gets wet'（正解）。 'If it is raining, the grass is getting wet'（特定の瞬間であって、一般的なルールじゃない）。 - Confusing 'if' and 'when': このルールでは、これらはほぼ同じだよ。でも
whenの方が少し確実性が高い響きがあるかな。自然な感じにするために、これらを交換して使ってみて。
Contrast With Similar Patterns
Zero なのか First Conditional なのか、どうやって判断する？すべては「確実性のバイブス（Vibe of Certainty）」次第だよ。- Zero Conditional: 一般的で、常に真実。 'If I eat peanuts, I get sick.'（毎回、永遠に）。
- First Conditional: 特定的で、未来の可能性。 'If I eat this peanut, I will get sick.'（今まさに、この特定のナッツについて）。
- Present Simple vs. Will:
Zeroは現在にとどまる。Firstは未来を見る。 - Logic vs. Prediction:
Zeroは論理だ。Firstは予測だ。
Quick FAQ
unless は使える？
使えるよ！ Unless は「もし〜でなければ（if not）」って意味だ。 'Unless you pay, you don't get the food.'
フォーマルなの？
ニュートラルだよ！上司にも親友にも使えるよ。
過去の習慣にも使える？
過去の習慣には、両方のパートで Past Simple を使おう。 'If it rained, we stayed inside.' でもそれはまた別のお話！
Zero Conditional Structure
| Clause Type | Conjunction | Subject | Verb Tense | Example |
|---|---|---|---|---|
|
Condition Clause
|
If / When
|
I / You / We / They
|
Present Simple
|
If you heat...
|
|
Result Clause
|
(None)
|
I / You / We / They
|
Present Simple
|
...it melts.
|
|
Condition Clause
|
If / When
|
He / She / It
|
Present Simple (+s/es)
|
If it rains...
|
|
Result Clause
|
(None)
|
He / She / It
|
Present Simple (+s/es)
|
...the grass gets wet.
|
|
Negative Condition
|
If
|
I / You / We / They
|
Do not + Verb
|
If you don't eat...
|
|
Negative Result
|
(None)
|
I / You / We / They
|
Do not + Verb
|
...you don't grow.
|
Common Contractions in Zero Conditional
| Full Form | Contraction | Usage Example |
|---|---|---|
|
do not
|
don't
|
If you don't study, you fail.
|
|
does not
|
doesn't
|
If it doesn't rain, the plants die.
|
|
I am
|
I'm
|
If I'm late, I call.
|
|
it is
|
it's
|
If it's hot, I swim.
|
Meanings
A grammatical structure used to express general truths, scientific facts, or situations where one action always results in another.
Scientific Facts
Describing laws of nature or universal truths that never change.
“If water reaches 100 degrees, it boils.”
“If you drop an object, it falls to the ground.”
Personal Habits & Routines
Describing things you always do in response to a specific situation.
“If I wake up late, I miss the bus.”
“I always drink tea if I feel stressed.”
Instructions and Rules
Giving orders or explaining how things work in a specific system.
“If the light turns red, you stop.”
“If you have a question, raise your hand.”
Reference Table
| 使い方 | If/When節（条件） | 主節（結果） | 例 |
|---|---|---|---|
|
普遍の真理
|
現在形
|
現在形
|
If you freeze water, it turns to ice.
|
|
科学的事実
|
現在形
|
現在形
|
When you heat metal, it expands.
|
|
習慣・日課
|
現在形
|
現在形
|
If I get tired, I drink tea.
|
|
指示・規則
|
現在形
|
現在形（または命令形）
|
If the light is red, you stop.
|
|
原因と結果
|
現在形
|
現在形
|
When it rains, the ground gets wet.
|
|
どちらも使える
|
If または When
|
常に現在形
|
If/When you press the button, the machine starts.
|
フォーマル度スペクトル
If flora is deprived of hydration, it perishes. (Gardening)
If you don't water plants, they die. (Gardening)
No water, plants die. (Gardening)
If you ghost your plants, they're toast. (Gardening)
ゼロ条件文：普遍の真理
構造
- `If` / `When` + 現在形 条件節
- 現在形 結果節
用途
- 科学的事実 例: If you heat ice, it melts.
- 普遍の真理 例: When it rains, the grass gets wet.
- 習慣 / 日課 例: If I'm tired, I drink coffee.
- 指示 / 規則 例: When you click Save, it updates.
主な特徴
- 100% の確実性 常に起こる
ゼロ条件文における If vs. When
ゼロ条件文の判断
その条件が起こったとき、結果は「常に」真実ですか、それとも普遍的な事実/習慣ですか？
条件と結果の両方が、一般的な現在時制で起こっていますか？
その文は科学的事実、普遍の真理、日課、指示のいずれかを説明していますか？
日常生活におけるゼロ条件文
科学と自然
- • If you drop something, it falls.
- • When it gets cold, water freezes.
毎日の習慣
- • If I wake up early, I go for a run.
- • When I'm tired, I drink coffee.
テクノロジーと指示
- • If you press enter, it submits.
- • When the battery is low, the phone vibrates.
人間の行動
- • If people are happy, they smile.
- • When I'm stressed, I listen to music.
レベル別の例文
If you heat ice, it melts.
If you heat ice, it melts.
If I am hungry, I eat.
If I am hungry, I eat.
Water boils if it is hot.
Water boils if it is hot.
If it rains, I use an umbrella.
If it rains, I use an umbrella.
If you don't study, you fail.
If you don't study, you fail.
When it is cold, I wear a coat.
When it is cold, I wear a coat.
If my mom cooks, it tastes good.
If my mom cooks, it tastes good.
Does the dog bark if you knock?
Does the dog bark if you knock?
If you mix oil and water, they don't blend.
If you mix oil and water, they don't blend.
If the battery dies, the phone turns off.
If the battery dies, the phone turns off.
If I drink too much coffee, I get a headache.
If I drink too much coffee, I get a headache.
The machine works if you plug it in.
The machine works if you plug it in.
If a person exercises regularly, their health improves.
If a person exercises regularly, their health improves.
If the economy slows down, unemployment usually rises.
If the economy slows down, unemployment usually rises.
If you violate the terms of service, your account is suspended.
If you violate the terms of service, your account is suspended.
When a metal is heated, it expands.
When a metal is heated, it expands.
If one neglects their duties, consequences inevitably follow.
If one neglects their duties, consequences inevitably follow.
If the pressure increases, the volume of the gas decreases.
If the pressure increases, the volume of the gas decreases.
If a society prizes wealth over wisdom, it stagnates.
If a society prizes wealth over wisdom, it stagnates.
If the software encounters an error, it generates a log file.
If the software encounters an error, it generates a log file.
If the premise is flawed, the entire argument collapses.
If the premise is flawed, the entire argument collapses.
If a species fails to adapt to its environment, it faces extinction.
If a species fails to adapt to its environment, it faces extinction.
If the judiciary loses its independence, democracy is imperiled.
If the judiciary loses its independence, democracy is imperiled.
If light passes through a prism, it refracts into a spectrum.
If light passes through a prism, it refracts into a spectrum.
間違えやすい
Learners use 'will' in Zero Conditional because they think the result happens 'later'.
Learners aren't sure which one to use in the Zero Conditional.
Learners think they must always use a subject in the second clause.
よくある間違い
If you heat ice, it will melt.
If you heat ice, it melts.
If it rain, the grass gets wet.
If it rains, the grass gets wet.
If I am tired I sleep.
If I am tired, I sleep.
If you mix red and blue you got purple.
If you mix red and blue, you get purple.
When I will be hungry, I eat.
When I am hungry, I eat.
If you don't study you are failing.
If you don't study, you fail.
Does the water boils if you heat it?
Does the water boil if you heat it?
If the sun goes down, it became dark.
If the sun goes down, it becomes dark.
If you would heat water, it boils.
If you heat water, it boils.
If the alarm rings, you will leave.
If the alarm rings, leave.
If one should heat the element, it reacts.
If one heats the element, it reacts.
If the data are corrupted, the system will crash.
If the data are corrupted, the system crashes.
文型パターン
If you ___, you ___.
When it ___, I always ___.
If the ___ ___, the ___ ___.
___ happens if you ___.
Real World Usage
If you add acid to the base, the pH changes.
If the oil is hot, add the onions.
If you lift heavy weights, your muscles grow.
If you restart the router, the connection resets.
If you don't finish your vegetables, you don't get dessert.
If the light is red, you stop.
If I see a meme, I share it.
If a customer complains, we offer a refund.
「いつもそうなる」と考えてみて
「will」や「would」は使わないで
A common trap! Remember, both parts of the Zero Conditional (if/when clause and main clause) use the present simple.
確実なら「When」を使おう
ルールや説明に大活躍
The Zero Conditional is fundamental for stating rules, instructions, and general advice in English-speaking cultures.
Smart Tips
Check if you used 'will'. If you did, delete it! Facts don't need 'will'.
Swap 'if' for 'when' to describe your habits.
Use an imperative in the second clause for a direct, clear command.
Read the sentence aloud. If you naturally pause in the middle, you probably need a comma because the 'if' is at the start.
発音
The Comma Pause
When the 'if' clause comes first, there is a slight rising intonation followed by a brief pause at the comma.
Contraction Stress
In negative forms, the word 'don't' or 'doesn't' is usually stressed to emphasize the condition.
Conditional Rise-Fall
If you heat ice ⤴, it melts ⤵.
The rise indicates the condition is being set, the fall indicates the certain result.
暗記しよう
記憶術
Zero is for Zero Doubt: If it's a fact, keep the tense exact (Present + Present).
視覚的連想
Imagine a light switch. If you flip the switch (Condition), the light turns on (Result). It happens every single time, without fail.
Rhyme
If this is true, that is too; it's a fact for me and you.
Story
A scientist in a lab always follows the same steps. If she mixes A and B, she gets C. If she heats the liquid, it turns into gas. Her whole world is a Zero Conditional.
Word Web
チャレンジ
Write down 5 things that are always true about your daily routine using 'If' or 'When'. (e.g., 'If I drink coffee, I feel better.')
文化メモ
Brits often use the Zero Conditional to discuss the weather or social etiquette with a sense of 'unwritten rules'.
Commonly used in 'Life Hacks' or self-improvement culture to state 'rules for success'.
This is the 'language of logic'. Using 'will' instead of the Zero Conditional in a lab report can make a result seem like a lucky guess rather than a proven fact.
The term 'conditional' comes from the Latin 'condicionalis', meaning 'subject to a condition'.
会話のきっかけ
What happens if you don't drink water for a day?
Tell me a scientific fact you remember from school.
What are your personal 'rules' for a productive day?
How does your computer behave if it gets too hot?
日記のテーマ
よくある間違い
Test Yourself
If you ___ (mix) red and blue, you get purple.
Find and fix the mistake:
When it rains, the roads will get slippery.
正しい文を選びなさい:
英語に翻訳しなさい：「Si calientas hielo, se derrite.」
Answer starts with: ["I...
Score: /4
練習問題
8 exercisesIf you ___ (freeze) water, it ___ (become) solid.
Choose the correct option:
Find and fix the mistake:
If she drink coffee at night, she doesn't sleep well.
When I am late, my teacher gets angry.
You should use a comma if the 'if' clause comes at the end of the sentence.
A: What happens if you press this button? B: The machine ___.
if / you / die / don't / plants / water / them
1. If you mix red and yellow... | 2. If you heat ice... | 3. If you don't eat...
Score: /8
Practice Bank
12 exercisesWhen the doorbell ___ (ring), my dog always barks.
If you will study hard, you pass the exam.
正しい文はどれですか？
英語に翻訳しなさい：「Cuando me canso, tomo un descanso.」
これらの単語を並べ替えて文を作りなさい:
条件とその普遍的な結果を合わせなさい:
Unless you ___ (add) sugar, coffee tastes bitter.
If you will press 'undo', the last action is cancelled.
文法的に正しい文はどれですか？
英語に翻訳しなさい：「Si hace mucho calor, encendemos el aire acondicionado.」
これらの単語を並べ替えて文を作りなさい:
ゼロ条件文の文を完成させなさい:
Score: /12
よくある質問 (8)
Yes! In the Zero Conditional, they mean almost the same thing. 'When' suggests the condition happens regularly.
Generally, no. If you use `will`, it becomes a First Conditional, which is for a specific future event, not a general truth.
Yes, but you must use the Past Simple in both clauses. 'If it rained, we played inside.' This describes a past habit.
Zero is for *always* (facts). First is for *maybe* (future possibilities).
Only if the `if` clause comes first. If it's in the middle, no comma is needed.
Yes! You can use them in the result clause to state a rule. 'If you are 18, you can drive.'
It is neutral. It is used in both very formal scientific papers and very informal daily conversation.
Because there is 'zero' uncertainty. The result is 100% guaranteed by the condition.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
Si + presente + presente
Spanish speakers rarely make the 'will' mistake because they also use the present tense in the result.
Si + présent + présent
French may use 'quand' (when) more frequently than 'si' for these types of sentences.
Wenn + Präsens + Präsens
The verb moves to the end of the 'wenn' clause in German, unlike English.
Verb + と (to)
Japanese has several conditional forms (tara, ba, nara), but 'to' is the closest to the Zero Conditional.
Idha (إذا) + Present/Past
Arabic tense logic in conditionals doesn't always map 1:1 to English 'Present Simple'.
如果...就... (rúguǒ... jiù...)
The lack of verb endings means the 'Zero' aspect is understood through context rather than grammar.
Learning Path
Prerequisites
Continue With
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