Grammar Rule in 30 Seconds
Use 'I'd've' to talk about past regrets quickly and sound like a native speaker by fusing 'I would have'.
- Combine 'I + would + have' into 'I'd've' for fast speech. Example: 'I'd've called you.'
- Use 'hadn't've' for negative past conditions. Example: 'If I hadn't've gone, I'd've missed it.'
- Only use double contractions in informal writing or speaking; avoid them in formal essays.
Overview
Third Conditional（仮定法過去完了）の習得は避けて通れない重要なステップです。「もしあの時〜していたら、〜だっただろうに」という、過去の事実とは異なる仮定を述べるこの構文は、ビジネスや日常会話で非常に頻繁に使われます。しかし、教科書通りの If I had known, I would have told you というフルフォームだけで話していると、どうしても不自然で、堅苦しく、あるいは「教科書を読んでいる」ような印象を与えてしまいます。If I'd known, I'd've told you といった短縮形（Contractions）は、単なる省略ではなく、英語特有の「リズム」を維持するための不可欠な要素です。日本語には、助動詞や助詞を融合させて音を圧縮するような文法体系は存在しません。日本語は膠着語であり、助詞を一つずつ丁寧につなげていく言語ですが、英語は強勢拍リズム（Stress-timed language）を持つ言語であり、意味の核とならない機能語を極端に短縮する性質があります。このリズムを理解せずにフルフォームばかり使っていると、会話のテンポについていけず、相手に「英語がまだこなれていない」という印象を与えてしまいます。本稿では、この Third Conditional の短縮形を、日本語の文法と比較しながら徹底的に解説します。Third Conditional の短縮形を理解する鍵は、'd という記号が文脈によって二つの全く異なる意味を持つことを理解することにあります。日本語には「短縮して一つの音にする」という文法概念がないため、ここが最大のハードルとなります。- 1
If-clause における'd：ここでは'dはhadを指します。過去完了形を作るための助動詞です。例：If I'd gone=If I had gone。 - 2Main clause における
'd've：ここでは'dはwouldを指し、'veはhaveを指します。つまりwould haveの圧縮形です。例：I'd've gone=I would have gone。
gone, seen, knownなど）以外の助動詞は、音として弱く発音される傾向があります。特に would have は、速い会話の中では would の w が消え、have の h も消え、'd've（ダヴのような音）と一息で発音されます。日本語の「音節」意識では、「ダ・イ・ド・ハ・ヴ」と5音節で捉えてしまいますが、英語ではこれを1音節に近い感覚で処理します。この「音の圧縮」は、英語の Stress-timed というリズムを保つために必須の機能です。日本語の「てにをは」のように一語ずつ独立させるのではなく、機能語をくっつけてしまうこの感覚を身につけることが、B2レベルからさらに上の流暢さへ進むための鍵となります。If I'd known about the meeting, I'd've prepared the documents.'d は had、後の 'd've は would have を表しています。この使い分けを瞬時に判断できるようになるまで、何度も音読を繰り返すことが重要です。- カジュアルな会話・SNS: 友人とのLINEや、飲み会、カフェでの会話では、短縮形を使わないと逆に「怒っているのか？」「他人行儀だな」という印象を与えます。
I'd'veを使うことで、自然で親しみやすい雰囲気を演出できます。 - ビジネスでのチャット・社内メール: スラック（Slack）やチーム内でのメールであれば、短縮形は一般的です。効率を重視する職場環境では、
I wouldn't've missed the deadline if I'd checked the system.のように書くのが標準的です。 - 公式な文書・プレゼン: 一方、クライアントへの正式な提案書、大学の論文、公式なスピーチでは、短縮形は厳禁です。ここではフルフォームの
would haveを使うことで、誠実さと正確さを示します。
- 1
'dをすべてwouldと勘違いする: 日本語には「had」と「would」を短縮して同じ音にする文化がないため、混乱が生じます。If I'd goneを「もし私が〜するだろうに」と訳してしまうミスです。Ifの直後の'dは必ずhadです。 - 2
If-clause にwould haveを入れてしまう: 日本語の「もし〜しただろうなら」という言い回しに引きずられ、If I'd've known...と言ってしまう人が非常に多いです。これはネイティブも口語でやることがありますが、文法的には誤りです。Ifの中にはhadしか入りません。 - 3
'veを脱落させる:I'd helped himと言うと、これは「私は彼を助けていた（過去完了）」という意味になり、「助けてあげたのに（仮定法）」という意味が消えてしまいます。'veは仮定法であることを示す重要な標識ですので、必ず発音する必要があります。
Third Conditional と他の構文との比較です。Second Conditional の I'd go（もし行くなら行くのに）と Third Conditional の I'd've gone（もし行っていたら行ったのに）は、音の長さが全く違います。'd だけなら現在・未来の仮定、'd've なら過去の仮定、というふうに、音の塊（チャンク）として記憶してください。I'd've は本当に書くのですか？I'd not've と言わないのですか？not は助動詞と結合して wouldn't となるのが一般的だからです。wouldn't've という形が最も自然です。would have の have が弱化して v の音だけになっていることに注目してください。ダヴ という音を探す練習をしましょう。Third Conditional Structure
| Clause Type | Subject | Auxiliary 1 | Auxiliary 2 | Verb Form |
|---|---|---|---|---|
|
If Clause
|
If I
|
had
|
-
|
known (V3)
|
|
Result Clause
|
I
|
would
|
have
|
called (V3)
|
|
Contracted Result
|
I'd've
|
-
|
-
|
called (V3)
|
Common Double Contractions
| Full Form | Double Contraction | Pronunciation Guide |
|---|---|---|
|
I would have
|
I'd've
|
EYE-duv
|
|
You would have
|
You'd've
|
YOO-duv
|
|
He would have
|
He'd've
|
HEE-duv
|
|
She would have
|
She'd've
|
SHEE-duv
|
|
It would have
|
It'd've
|
IT-uh-duv
|
|
We would have
|
We'd've
|
WEE-duv
|
|
They would have
|
They'd've
|
THEY-duv
|
|
Would not have
|
Wouldn't've
|
WOOD-unt-uv
|
Meanings
The third conditional describes a past situation that did not happen and imagines the result of that imaginary past. Contractions make this complex structure easier to say in rapid conversation.
Expressing Regret
Using the contracted form to show sadness or disappointment about a past event that cannot be changed.
“I'd've told her the truth if I'd had the chance.”
“We'd've arrived on time if the train hadn't been late.”
Hypothetical Relief
Using the structure to express relief that a negative outcome was avoided.
“I'd've been so embarrassed if you hadn't warned me.”
“They'd've lost all their money if they'd invested then.”
Criticism of Others
Using the third conditional to point out what someone else should have done differently.
“He'd've passed the exam if he'd actually studied.”
“You'd've seen the sign if you'd been paying attention.”
Reference Table
| 代名詞 | 完全形 (主節) | 短縮形 (主節) | 例文 |
|---|---|---|---|
|
I
|
I would have
|
I'd've
|
If I'd known, I'd've helped.
|
|
You
|
You would have
|
You'd've
|
You'd've loved that concert.
|
|
He
|
He would have
|
He'd've
|
He'd've called if he could.
|
|
She
|
She would have
|
She'd've
|
She'd've passed easily.
|
|
It
|
It would have
|
It'd've
|
It'd've been a disaster.
|
|
We
|
We would have
|
We'd've
|
We'd've gone if it rained.
|
|
They
|
They would have
|
They'd've
|
They'd've seen us there.
|
フォーマル度スペクトル
If I had possessed the funds, I would have purchased the property. (Real estate)
If I'd had the money, I would have bought the house. (Real estate)
If I'd've had the cash, I'd've bought the place. (Real estate)
If I'da had the dough, I'da copped it. (Real estate)
仮定法過去完了の短縮形: クイックガイド
If節 (過去完了)
- had 'dと短縮される
- If I'd known If I had known
- If she'd gone If she had gone
主節 (完全条件)
- would have 'd'veと短縮される
- I'd've gone I would have gone
- They'd've helped They would have helped
否定の短縮形
- hadn't had not
- wouldn't've would not have
- If he hadn't... If he had not...
使い方と文脈
- インフォーマル 会話、メッセージ、SNS
- 流暢 自然な話し方を表す
- フォーマルでは避ける 論文、専門文書
仮定法過去完了の短縮形を使うタイミング
仮定法過去完了の短縮形を使うべき？
過去の仮説的な出来事や後悔を表現していますか？
文脈はインフォーマルですか（チャット、友達、SNSなど）？
「if」節（過去完了）ですか？
主節（完全条件）ですか？
仮定法過去完了の短縮形: 代名詞の力
If節の短縮形 ('had')
- • If I'd known...
- • If you'd told...
- • If he'd arrived...
- • If she'd seen...
- • If it'd worked...
- • If we'd tried...
- • If they'd left...
主節の短縮形 ('would have')
- • I'd've gone.
- • You'd've said.
- • He'd've helped.
- • She'd've passed.
- • It'd've been.
- • We'd've won.
- • They'd've called.
否定の短縮形
- • If I hadn't known...
- • I wouldn't've gone.
- • He couldn't've done it.
- • She shouldn't've said that.
レベル別の例文
I would have liked that.
Me habría gustado eso.
If I had time, I would go.
Si tuviera tiempo, iría.
I'd like a coffee.
Me gustaría un café.
She would have been happy.
Ella habría estado feliz.
If I'd seen him, I'd have said hello.
Si lo hubiera visto, le habría dicho hola.
We'd have won if we played better.
Habríamos ganado si hubiéramos jugado mejor.
I wouldn't have gone if it rained.
No habría ido si hubiera llovido.
He'd have called you later.
Él te habría llamado más tarde.
If I'd known the truth, I'd have acted differently.
Si hubiera sabido la verdad, habría actuado de forma diferente.
You'd have loved the movie we saw.
Te habría encantado la película que vimos.
They'd have finished if they hadn't stopped.
Habrían terminado si no hubieran parado.
I'd've helped you if you'd asked.
Te habría ayudado si me lo hubieras pedido.
I'd've been there in a heartbeat if I'd've known you were in trouble.
Habría estado allí en un abrir y cerrar de ojos si hubiera sabido que estabas en problemas.
If the company hadn't've gone bankrupt, I'd've stayed there forever.
Si la empresa no hubiera quebrado, me habría quedado allí para siempre.
She'd've definitely said yes if you'd've asked her out.
Ella definitivamente habría dicho que sí si le hubieras pedido salir.
We'd've never met if I hadn't've taken that specific flight.
Nunca nos habríamos conocido si no hubiera tomado ese vuelo específico.
Had the circumstances been different, I'd've likely pursued a different career path.
Si las circunstancias hubieran sido diferentes, probablemente habría seguido otra carrera.
I'd've thought that someone with your experience wouldn't've made such a mistake.
Habría pensado que alguien con tu experiencia no habría cometido tal error.
If I'd've known then what I know now, I'd've invested every penny in that startup.
Si hubiera sabido entonces lo que sé ahora, habría invertido cada centavo en esa startup.
He'd've been the perfect candidate if he hadn't've been so arrogant during the interview.
Él habría sido el candidato perfecto si no hubiera sido tan arrogante durante la entrevista.
It's a counterfactual scenario, but one could argue that the empire wouldn't've collapsed so abruptly had the succession been clearer.
Es un escenario contrafactual, pero se podría argumentar que el imperio no habría colapsado tan abruptamente si la sucesión hubiera sido más clara.
I'd've been remiss if I hadn't've mentioned the contributions of the junior staff.
Habría sido negligente si no hubiera mencionado las contribuciones del personal subalterno.
The project would've've (rare triple) succeeded if the funding hadn't've been pulled.
El proyecto habría tenido éxito si no se hubiera retirado la financiación.
Were it not for your intervention, I'd've surely succumbed to the pressure.
Si no fuera por tu intervención, seguramente habría sucumbido a la presión.
間違えやすい
Both 'would' and 'had' contract to ''d'.
They sound identical in speech.
よくある間違い
I would of go.
I would have gone.
If I would have seen him...
If I had seen him...
I'd've know.
I'd've known.
If I'd've known, I'd've did it.
If I'd've known, I'd've done it.
文型パターン
If I'd've known ___, I'd've ___.
I wouldn't've ___ if I'd've ___.
Real World Usage
I'd've texted u but my phone died.
If I'd had more time, I'd have finished the project.
I wouldn't've bought this if I'd known it was broken.
I'd've loved to be there! Looks fun!
We'd've seen the Eiffel Tower if we'd've stayed longer.
He'd've scored if he'd've taken the shot earlier!
「've」の音に耳を澄まそう
フォーマルとインフォーマル
Avoid them in formal academic writing.
発音練習
If I'd known, I'd've gone repeatedly."ネイティブのような響き
Using these contractions correctly is a huge step towards sounding like a native speaker.
文脈が重要
Smart Tips
They are likely saying 'I'd have' or 'I'd've'. Look at the context to see if they are talking about a regret.
Use 'I'd've' to save space and sound more like a friend than a textbook.
Ignore it! It's a mistake. Always remember it's 'would have'.
Try to say 'I'd've' in one single breath without pausing between the words.
発音
The Schwa Reduction
The 'have' in 'I'd've' is reduced to a tiny 'uv' sound (/əv/).
The 'D' Link
The 'd' from 'would' often links directly to the 'v' of 'have'.
Regretful Fall
I'd've ↘ gone.
Conveys a sense of sadness or finality about the past.
暗記しよう
記憶術
I'd've rhymes with 'I dive' into the past.
視覚的連想
Imagine a time machine with three buttons: 'I', 'Would', and 'Have'. When you press them all at once, the machine glows and says 'I'd've'!
Rhyme
If I'd've known, I'd've shown, but the chance has flown.
Story
A man named 'Ida' (I'd've) always regrets things. He says, 'If I'd've bought that ticket, I'd've been a millionaire.' He lives in the past, always using his double-contraction name.
Word Web
チャレンジ
Think of three things you regret from last week. Say them out loud using 'I'd've' as fast as you can.
文化メモ
In the Southern US, you might hear 'I'd'a' instead of 'I'd've'. It is very informal.
British speakers use double contractions frequently in casual conversation, especially in London and the North.
Aussies often shorten these even further, almost swallowing the 'have' entirely.
The Third Conditional developed in Middle English as the subjunctive mood became less distinct.
会話のきっかけ
If you'd've been born in a different country, how'd've your life been different?
If you'd've known about the pandemic in 2019, what'd've you done differently?
What's a movie you'd've liked to star in if you'd've been an actor?
日記のテーマ
よくある間違い
Test Yourself
If you ___ asked, I'd've helped you.
Find and fix the mistake:
If she'd've studied, she'd've passed the test.
Choose the correct sentence:
Translate into English: 'Si yo hubiera sabido, habría ido.'
Answer starts with: ["I...
Score: /4
練習問題
8 exercisesIf I'd seen the sign, ___ stopped.
Find and fix the mistake:
I would of called you if I'd've known you were home.
Choose the best option.
If I'd studied, ___.
Match 'She would have'
You can use 'I'd've' in the 'if' clause in formal writing.
A: Why didn't you come? B: If I'd known it was your birthday, ___.
Select the correct one.
Score: /8
Practice Bank
12 exercisesIf she'd seen the warning, she ___ avoided the accident.
We'd've finished on time if we'd've started earlier.
Choose the correct sentence:
Translate into English: 'Si ella no hubiera estado ocupada, nos habría acompañado.'
Arrange these words into a sentence:
Match the full forms with their contracted equivalents:
I ___ bought it if it'd been on sale.
If it'd've rained, the game would've been cancelled.
Which sentence is correct?
Translate into English: 'Nosotros no habríamos terminado si no hubieras ayudado.'
Arrange these words into a sentence:
Match the subjects with their 'would have' contractions:
Score: /12
よくある質問 (8)
It is a 'double contraction'. While not a single word in the dictionary, it is a standard part of spoken English and informal writing.
Because 'would've' and 'would of' sound exactly the same. It is a very common mistake made by native speakers.
It's better to use 'I would have' or 'I'd have' to remain professional. 'I'd've' is very casual.
'I'd' can mean 'I would' or 'I had'. 'I'd've' specifically means 'I would have'.
It sounds like 'WOOD-unt-uv'. The 'h' in 'have' is completely silent.
Yes, it is very common in all major dialects of English, including British, American, and Australian.
Yes! You can say 'could've' or 'should've'. Double contractions like 'shouldn't've' are also common.
Yes, in the third conditional, it always refers to an imaginary past situation.
Scaffolded Practice
1
2
3
4
Mastery Progress
Needs Practice
Improving
Strong
Mastered
In Other Languages
Si hubiera sabido, habría ido.
Spanish has no equivalent to the double contraction 'I'd've'.
Si j'avais su, je serais venu.
French cannot contract 'je' and 'serais' into a single sound like English.
Wenn ich es gewusst hätte, wäre ich gekommen.
German uses 'hätte' (had) or 'wäre' (were) depending on the verb, whereas English mostly uses 'would have'.
Shitteitara, itteita noni.
Japanese has no auxiliary verbs like 'would' or 'have' to contract.
Law kuntu a'lam, lakuntu dhahabt.
Arabic grammar is based on particles and prefixes, not auxiliary stacking.
Rúguǒ wǒ zǎo zhīdào, wǒ jiù qùle.
Chinese has no verb conjugation, so the entire concept of 'would have been' is expressed through context.
Learning Path
Prerequisites
Learn These First
関連動画
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