第10讲：时态 (二)

　　时态的运用比较复杂，好多同学因为做题时不知应用哪种时态而挠头皮。其实你只要把易混的时态掌握好，对你来说时态就没有什么难点可言了。而你易混的时态无非是一般过去时和现在完成时，一般过去时和过去完成时的比较罢了。这有何难?看看下面的分析，你会发现一切"as easy as A B C"。

　　一般过去式和现在完成时：

　　一般过去式只是表示事情发生在过去，陈述一个事实，它可以和确定的表示过去的时间状语如：last night, in 1999, three days ago等连用。而现在完成时表示某一完成的动作对现在造成的影响或结果，强调的是现在的情况，所以它不能和确定的表示过去的时间状语连用。

　　如： We have seen that film. 我们已看过那部电影。 对现在造成的影响是我们对影片已有所了解。 We saw the film last night. 昨天晚上我们看了那部电影。只说明昨天晚上看电影这一事实。

　　注意：有些时间状语，如this morning,tonight, this month 等，既可用于一般过去时，又可用于现在完成时，但所表达的意义有所不同。用于现在完成时表示包括现在在内，而用于一般过去式则与现在无关。如： I have read this book this April.(说话时仍然为四月。)  I read this book this April. (说话时四月份已过。)

　　一般过去式和过去完成时的比较：

　　一般过去式表示过去时间发生的动作或存在的状态，而过去完成时在过去某一时间或动作之前已完成的动作或状态，即"过去的过去"。当强调过去某一动作发生在某一动作之前时，常用此时态。

　　如： He had finished his homework before nine o'clock.　九点之前他已经完成了作业。实际上，一般现在时和过去完成时常搭配使用。如： When he got home, his daughter had already gone to bed. 当他到家的时候，他的女儿早已去睡觉了。

　　在带有after和before引导的时间状语从句的复合句中，由于从句的动作和主句的动作发生的先后顺序已经非常明确，所以可以用一般过去时代替过去完成时。　如：He called on me soon after he had finished his homework. 他做完作业后不久便来拜访我。也可以说： He called on me soon after he finished his homework.

　　哇塞，我们终于学完了所有时态，摩拳擦掌，试试趁热打铁！

　　练习：

　　1. Zhao Lan ____ already ___ in this school for two years.

　　A. was...studying

　　B. will ... study

　　C. has ...studied

　　D. are studying

　　2. They usually _____ TV in the evening.

　　A. watch

　　B. will watch

　　C. are watching

　　D. watches

　　3. Judy _____ the Great Wall twice, and now she still ______ to go there.

　　A. went to , wanted

　　B. goes to , wants

　　C. has gone , wants

　　D. has been to, wants

　　4. She will find him a kind man when she _______ more about him.

　　A. knows

　　B. know

　　C. will know

　　D. is going to know

　　5. --What are you going to give our teacher for Teacher's Day?

　　--I'm not sure. Maybe I _____ him some flowers.

　　A. have given

　　B. will give

　　C. gave

　　D. give

　　6. --Tom ______ out.

　　--Oh, is he? What time _____ he _____ out?

　　A. is, did, go

　　B. went, is ,going

　　C. has gone, did, go

　　D. is going, does, go

　　7. It's nine o'clock now, they ______ an English class.

　　A. have

　　B. are having

　　C. having

　　D. will have

　　8. --" Where is Li Lei?"

　　--" He _______ his sports shoes in the room. He ______ football with his friends."

　　A. is putting on , is playing

　　B. puts on, will play

　　C. is putting on , will play

　　D. put on, played

　　9. Miss Smith with her parents ______ China since _________.

　　A. have been in , two years ago

　　B. has gone to, two years

　　C. have been to, two years

　　D. has been in, two years ago

　　10. When I knocked at the door, my mother _______.

　　A. is cooking

　　B. cooked

　　C. was cooking

　　D. cooks