精品文档
1. （2005 天津卷） By the time Jane gets home , her aunt ______ for London to attend
a meeti ng.
A. will leave
B. leaves
C. will have left
D. left
［解析］答案为C o从gets home可知Jane还未回到家，等到 Jane在将来的某个时
间回到家以前，她的aunt将已经赴伦敦参加一个会议去了，故用将来完成时。
2. （ 2008 四川卷）The telephone ___ ，but by the time I got in doors ，it stopped.
A. had rung
B. was ringing
C. rings
D. has rung
［解析］答案为B o进门之前电话铃一直在响，但当我进门的时候，它停止了。but 前面分句的动作是先发生的，而且延续的时间较长，故用was ringing 。
3. （2008 山东卷） By the time he realizes he ______ i nto a trap , it 'l be too late for him to do any thi ng about it.
A. walks
B. walked
C. has walked
D. had walked
［解析］答案为C o主句用了一般将来时，根据时态一致原则排除B和D o根据句意
截止到他意识到的时候，他已经走进了一个陷阱”可知，空档最好填现在完成时。
4. （2009 北京卷） When I talked with mygrandma on the phone, she sounded weak,
but by the time we ___ up , her voice had bee n full of life.
A. were hanging
B. had hung
C. hung
D. would hang
［解析］答案为C o当我与祖母通电话时，她听起来很虚弱，但是当我们挂断电话的
时候，她的声音已经充满活力。by the time 后的主句用了过去完成时，因此空档处最好
用一般过去时。
5. （2011 辽宁卷） By the time Jack returned homefrom England , his son _______ from college.
A. graduated
B. has graduated
C. had bee n
D. had graduated
［解析］答案为Dt截止到Jack从英国返家，他的儿子已经大学毕业了。回家用了
一般过去时，大学毕业发生在过去的过去，故用过去完成时。
by the time 意为到..... 时候（为止）”是一个介词短语，在句中经常起连词作用，
引导时间状语从句。它的主要用法如下：
1. 如果从句中的谓语动词是一般过去时，那么主句中的谓语动词通常用过去完成时，
表示截止到从句动作发生时，主句动作已经完成，即过去的过去”例如：
By the time he was fourteen years old , Einstein had learned advaneed mathematics all by himself. 到14岁的时候，爱因斯坦就已经自学完了高等数学。
By the time he returned home , the rain had stopped. 等他回至U家时，雨已经停了。
2. 如果从句中的谓语动词为一般现在时（表示将来），那么主句中的谓语动词常为将来
完成时，表示截止到将来某一时间为止，主句动作将已经完成”例如：
By the time John finishes his homework, his classmates shall have left to play football. 到约翰做完作业时，她的同学将已离开去伦踢足球了。
By the time you get back , I shall have fi nished the work. 到你回来时，我将
已经把活做完了。
3. 如果主句动作不强调已经完成，只是说明过去某个时候的状况，此时主句不用完成
时，而应根据实际需要选用适当的时态，此时by the time 相当于when。例如：He was out of breath by the time he reached the top. 登上顶端时，他气喘吁吁。
By the time the bus came, so many people were waiting that it was a free fight 公共汽车来的时候，等车的人很多，成了一场挤车的混战。
to get on it.