| 时态 | 从句谓语动词 | 主句谓语动词 |
|---|---|---|
| 现在 | \(\text{did/were}\) | \(\text{would/coud/should/might + do}\) |
| 过去 | \(\text{had done}\) | \(\text{would/coud/should/might + have done}\) |
| 将来 | \(\text{did/were, were to do, should do}\) | \(\text{would/coud/should/might + do}\) |
if 的虚拟语气和省略形式
| 时态 | 从句谓语动词 | 主句谓语动词 |
|---|---|---|
| 现在 | \(\text{did/were}\) | \(\text{would/coud/should/might + do}\) |
| 过去 | \(\text{had done}\) | \(\text{would/coud/should/might + have done}\) |
| 将来 | \(\text{did/were, were to do, should do}\) | \(\text{would/coud/should/might + do}\) |