【语法——时态（2）】，学习英语的话英语可是很重要的哦，大家赶紧来5068频道看看浅陌带给大家的语法总结吧。
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 初中化学 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.
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
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