:
e.He has been in the League for three years. （在团内的状态可延续）
f.He has been a League member for three years. （是团员的状态可持续）
句子中如有过去时的时间副词（如yesterday, last, week, in 1960）时，不能使用现在完成时，要用过去时。
（错）Tom has written a letter to his parents last night.
（对）Tom wrote a letter to his parents last night.
用于现在完成时的句型
1）It is the first / second time.... that…结构中的从句部分，用现在完成时。例如：
It is the first time that I have visited the city. 这是我第一次访问这城市。
This is the first time （that） I've heard him sing. 这是我第一次听他唱歌。
注意：It was the third time that the boy had been late.
2）This is +形容词最高级+that…结构，that 从句要用现在完成时。例如：
This is the best film that I've （ever） seen. 这是我看过的最好的电影。
