我们需要特别注意以下几种情况和句型结构：
1.一般现在时可以代替将来时，用于时间和条件状语从句中。例如：
　　1)Return the book immediately to the library as soon as you _____ it.
　　　 A. finish
　　　 B. are finished
　　　 C. have finished
　　　 D. are finishing
　　答案A。
　　2)Please be sure to telephone me the next time you _____.
　　　 A. will come
　　　 B. would come
　　　 C. shall come
　　　 D. come
　　答案D。
　　2.在“This is the first time…”结构中，后面的从句用现在完成时。
　　句子开头也可以用it代替this
　　例：This is the first time that I have met Jane.
　　3.在“It/This is +形容词最高级+名词后面的从句中，用现在完成时。”
　　例：This is one of the best books _____ on the subject.
　　　 A. that have ever been written
　　　 B. which have ever been written
　　　 C. that has ever been written
　　　 D. whatever have been written
　　答案为A。
　　4.在“It is/has been＋时间段＋since…后边用过去时。”
　　例：It has been twenty years since I left my hometown.
　　5.在“no sooner…than”和“hardly… when…”结构中，主句部分用过去完成时，从句部分用过去时。例如：
　　1)I had no sooner returned than he called.
　　2)We had hardly begun when we were told to stop.
　　6.在“It is (high) time后边的从句中用过去时。”
　　例：It is time that we had a rest.

7. 时态与时间状语 ：