预约成功
八、过去完成时
1、表示在过去的某一时间或动作之前已经完成了的动作(即过去的过去)。这个过去的某一时间可用by, before等介词或连词引导的短语或一个从句来表示。
例：About the sixth century A.D. when few Europeans could read, the Chinese _____ paper.
A. invented B. had invented C. have invented D. had been invented
(答案：B)(1997年35题)
2、表示从过去某一时间开始，一直持续到另一个过去的时间的动作。
例：The chemistry class _____ for five minutes when we hurried there.
A. had been on B. was on C. has been on D. would be on
(答案：A)(1995年24题)
3、在含有before, after, as soon as 等连词引导的状语从句的复合句中，由于连词本身可以明确表示动作发生的先后顺序，因此，主句和从句都可以用一般过去时表示，而不用过去完成时。
例：I called him as soon as I arrived.我刚一到就给他打电话。
4、过去完成时常用在no sooner …than…, hardly/scarcely/barely…when…，一…就…。句型之中，句子到装。
(1)No sooner had we sat down _____ we found it was time to go.
A. than B. when C. as D. while
(答案为A)(1997年50题)
(2)Scarcely had he opened the door when a gust of wind blew the candle out. 他刚打开门，蜡烛就被一阵风吹灭了。
九、将来完成时：表示在将来某一时间以前完成的动作。
1、By the time John gets home, his aunt _____.
A. will have B. leaves C. will have left D. is leaving
(答案：C)(1995年25题)
2、I _____ writing the article by the time you get back.
A. shall finish B. must have finished C. have finished D. shall have finished (答案：D) (2000年24题)
十、现在完成进行时：表示从过去某时一直延续到现在的一个动作，这个动作一般会继续延续下去，或是到说话时结束， 但是强调到说话时为止一直在做的动作。
例：I _____ on the door for ten minutes now without an answer.
A. was knocking B. am knocking C. knocking D. have been knocking
(答案：D)(1998年49题)
