上海市普陀区政府领导:英语中的完成时是怎么样??句型呢?

现在完成时：主语+have/has+动词过去分词+宾语
过去完成时：主语+had+动词过去分词+宾语

现在完成时

现在完成时用来表示之前已发生或完成的动作或状 态，其结果的确和现在有联系。动作或状态发生在过去 但它的影响现在还存在；也可表示持续到现在的动作或 状态。其构成： have (has) +过去分词。

用于现在完成时的句型

1）It is the first / second time…. that…结构中的从句部分，用现在完成时。
It is the first time that I have visited the city.
It was the third time that the boy had been late.

2）This is the… that…结构，that 从句要用现在完成时.
This is the best film that I've (ever) seen.
这是我看过的最好的电影。
This is the first time (that) I've heard him sing. 这是我第一次听他唱歌。

典型例题
(1) ---Do you know our town at all?
---No, this is the first time I ___ here.
A. was B. have been C. came D. am coming
答案B. This is the first time 后面所加从句应为现在完成时，故选B。

(2) ---Have you ____ been to our town before?
---No, it's the first time I ___ here.
A. even, come B. even, have come C. ever, come D. ever, have come
答案D. ever意为曾经或无论何时，反意词为never，此两词常用于完成时。 This is the largest fish I have ever seen. It is / was the first time +that-clause 的句型中，从句要用完成时。
注意：非延续性动词的否定形式可以与表示延续时间的状语连用。即动作不发生的状态是可以持续的。
（错）I have received his letter for a month.
（对）I haven't received his letter for almost a month.

过去完成时

1） 概念：表示过去的过去
----|-------|-----|---->其构成是had +过去分词构成。
那时以前 那时 现在

2） 用法
a. 在told, said, knew, heard, thought等动词后的宾语从句。
She said (that) she had never been to Paris.
b. 状语从句
在过去不同时间发生的两个动作中，发生在先，用过去完成时；发生在后，用一般过去时。
When the police arrived, the thieves had run away.
c. 表示意向的动词，如hope, wish, expect, think, intend, mean, suppose等，用过去完成时表示"原本…，未能…"
We had hoped that you would come, but you didn't.

3) 过去完成时的时间状语before, by, until , when, after, once, as soon as。
He said that he had learned some English before.
By the time he was twelve, Edison had began to make a living by himself.
Tom was disappointed that most of the guests had left when he arrived at the party.

典型例题
The students ___ busily when Miss Brown went to get a book she ___ in the office.
A. had written, left B，were writing, has left C. had written, had left D. were writing, had left
答案D. "把书忘在办公室"发生在"去取书"这一过去的动作之前，因此"忘了书"这一动作发生在过去的过去，用过去完成时。句中when表示的是时间的一点，表示在"同学们正忙于……"这一背景下，when所引导的动作发生。因此
前一句应用过去进行时。

注意： had no … when 还没等…… 就……
had no sooner… than 刚…… 就……
He had no sooner bought the car than he sold it.

将来完成时

1) 构成will / be going to do sth.
2) 概念
a. 状态完成：表示某事继续到将来某一时为止一直有的状态。
b. 动作完成：表示将来某一时或另一个将来的动作之前，已经完成的动作或一获得的经验。
They will have been married for 20 years by then.
You will have reached Shanghai by this time tomorrow.

完成时主要有以下几种：
1.现在完成时，表示已完成的事对现在造成的影响
句型：sb have done sth 理解为某人完成了某事

2.过去完成时，表示在过去完成的并对过去产生的影响，特征是句尾＋BY或when引导的表示过去时间短语或句子
句型：sb had done sth when he was five
理解为 早在他5岁时，就已经完成某事

3.将来完成时，依此类推，表示将来完成的动作并对将来产生影响，句尾接表将来的时间短语或句子
句型为 sb will have done sth in 2050
表示 到2050年，某人将会完成某事

将来完成时和一般将来时功能类似，只是起到强调作用

现在完成时是由：have+过去分词（动词的第三式）构成的。
这种时态只关心的是现在的结果，或者是过去的事情对现在发生的影响 。所以，现在完成时可以理解成是回顾到过去的现在时。
Have you ever been to shanyang?
就是说到目前为止你去过没有。

过去完成时是由：had +过去分词构成的。

过去完成时主要用在从句中，表示两件事情哪件事情发生较早。
when i came,tom had already gone.

http://www.exam8.com/englishlearning/grammar/