2010-05-07 04:10:00
四、 过去进行时：
1.概念：表示过去某段时间或某一时刻正在发生或进行的行为或动作。
2.时间状语：at this time yesterday, at that time或以when引导的谓语动词是一般过去时的时间状语等。
3.基本结构：was/were+doing
4.否定形式：was/were + not + doing.
5.一般疑问句：把was或were放于句首。
6.例句：At that time she was working in a PLA unit.
When he came in, I was reading a newspaper.
五、 现在完成时：
1.概念：过去发生或已经完成的动作对现在造成的影响或结果，或从过去已经开始，持续到现在的动作或状态。
2.时间状语：recently, lately, since…for…,in the past few years, etc.
3.基本结构：have/has + done
4.否定形式：have/has + not +done.
5.一般疑问句：have或has。
6.例句：I've written an article.
The countryside has changed a lot in the past few years.
六、 过去完成时：
1.概念：以过去某个时间为标准，在此以前发生的动作或行为，或在过去某动作之前完成的行为，即“过去的过去”。
2.时间状语：before, by the end of last year(term, month…),etc.
3.基本结构：had + done.
4.否定形式：had + not + done.
5.一般疑问句：had放于句首。
6.例句：As soon as we got to the station, the train had left.
By the end of last month. We had reviewed four books
七、 一般将来时：
1.概念：表示将要发生的动作或存在的状态及打算、计划或准备做某事。
2.时间状语：tomorrow, next day(week, month, year…),soon, in a few minutes, by…,the day after tomorrow, etc.
3.基本结构：am/is/are/going to + do；will/shall + do.
4.否定形式：was/were + not; 在行为动词前加didn't，同时还原行为动词。
5.一般疑问句：be放于句首；will/shall提到句首。
6.例句：They are going to have a competition with us in studies.
It is going to rain.