定義 / 解説
third conditional は、変えられない過去について「もし〜だったら、〜だっただろう」を述べる構文です。過去の非現実条件と、その非現実結果をセットで表します。後悔、批判、振り返り、説明でよく使われます。現実の出来事と別の可能性を対比するため、 first / second より複雑に感じられます。
主要ルール
- 形: if + had + past participle, would have + past participle。
- 過去の非現実条件 + 過去の非現実結果を表す。
- 節の順序は入れ替え可能で意味は同じ。
- 結果節には could have、might have も使える。
- 標準英語では if 節に would have を置かない。
例文
- If I had studied, I would have passed. - もし勉強していたら、合格していたでしょう。
- She would have come if she had known. - もし知っていたら、彼女は来ていたでしょう。
- If they had left earlier, they could have caught the train. - もっと早く出ていれば、電車に間に合ったでしょう。
- We might have won if we had played better. - もっと良いプレーをしていれば、勝てたかもしれません。
- If you had called me, I would have helped. - もし電話してくれていたら、私は助けていたでしょう。
よくある間違い
- ❌ If I would have studied, I would have passed. -> ✅ If I had studied, I would have passed.
- ❌ She would have come if she would have known. -> ✅ She would have come if she had known.
- ❌ If they had left earlier, they would caught the train. -> ✅ If they had left earlier, they would have caught the train.