1. 表示过去发生或已经完成的某一动作对现在造成的影响或结果。
[例句] —Have you had your supper yet? —Yes, I have just had it.
2. 常与介词for, during, in, within, over等引导的时间状语连用, 表示过去的某一行为一直延续到现在。
[例句] I haven’t seen my English teacher for a long time.
3. 表示反复或习惯性的动作, 常与several times, once, twice, frequently等频度副词连用。
[例句] I have been to the USA several times.
4. 表示从过去到现在没有发生过的动作。
[例句] I haven’t swept the floor for a week.
5. 用在时间、条件状语从句中, 表示从句动作先于主句动作完成。
[例句] I’ll tell him after you have left.
6. 在"级+ 名词"或在"这是第几次…"之后跟定语从句,从句用现在完成时。
[例句] ①This is the third time I have been there.
②This is the best tea I have ever drunk.