`17`. I could have helped you if you had told me about your problem.
`18`. Had I had enough money, I could have bought the novel.
`19`. If my father were here, he could give us some advice.
`20`. If I were you, I would stop smoking.
`21`. Unless you work harder, you will be sacked.
`22`. If he had known the road was bad, he wouldn't have driven very fast.
`23`. If I were you, I wouldn't drink that wine.
`24`. If you had had breakfast this morning, you wouldn't be hungry now.
`25`. If we hadn't spent too much last month, we would have money letf.
`26`. Were they strong enough, they could lift the table.
`27`. If they hadn't been talking, they wouldn't have missed the turn.
`28`. If he hadn't been sleeping, he could have heard the knock at the front door.
`29`. If the professor hadn't been speaking too fast, I could have understood everything.
`30`. Unless we had more rain, our crops couldn't grow.
+) Giải thích:
- Unless = If not
- Câu điều kiện loại 2: If + S + Ved/V2, S + would/could/might + V.
- Đảo ngữ câu điều kiện loại 2: Were + S (to V) + O, S + would/could/might + V.
- Câu điều kiện loại 3: If + S + had + PII/Ved + O, S + would/could/might + have PII/Ved.
- Đảo ngữ câu điều kiện loại 3: Had + S + PII/Ved, S + would/could/might + have PII/Ved.
- Câu điều kiện hỗn hợp loại 1: If + S + had + PII/Ved, S + would/could/might + V.
