1. Zero conditional
- talk about facts / some thing which is always true（诉说一个事实的时候）
- If + Present Simple
- Ex：If you heat the ice，it melts.
2. First Conditional
- talk about possible result in the future. （未来也许会发生的事情）
- If+ present simple+future
- Ex: If you study hard now, you will pass in the exam.
3. Second Conditional
- talk about something impossible or highly unlikely to happen. （几乎不可能发生的事情）
- If + past simple – would/wouldn’t + base verb
- Ex：If I was a student. I would study hard.
4. Third Conditional
- to talk about regrets and wishes （讲述后悔/希望会发生的事情）
- If + past perfect-would have + verb in past participle
- Ex: If I had studied hard. I wouldn’t have failed in the final examination.
5. Future Perfect
- completed action in the future
- will have + past participle
- Ex: He will have done it by this evening.
- Future Continuous
- will be happening in the future
- will be +verb-ing
- keywords：by the time、this time next year
6. Present Perfect Simple
- have/has+past participle
- keywords : just , yet , already
- Ex : She haven’t done her homework yet.
7.Present Perfect Continous
- have/has been + verb ting.
- keywords：since , for
- Ex: She has been doing homework for 2 hours.
8.wish for Present/Future
- wish + past simple
- Ex：I wish I was rich. (present)
- Ex：I wish it would stop. (past)