英语语法-完成时
现在完成时(一)：开始于过去的动作一直持续到现在，有可能继续持续。谓语动词为延续性动词
I have lived here for 3 years. 我仍然住在这里，而且还可能继续住下去。
如果在搬家时说这句话，则live这件事只持续到目前为止。
The teacher has taught in this school since I came here.
I’ve worked in this company since I left school.
since表明了动作开始的时间点。
有上下问明确告知，动作只持续到说话的时刻为止。
a. A: Have you waited long?
B: I’ve waited for three hours.
b. I’ve waited for him all day; I don’t want to wait any longer.
特点：
谓语动词为延续性动词
动作的发生时间是过去，持续到现在，还可能继续持续下去。
常常与表示一段时间的时间状语连用，是说明某个状态持续了多久。
与现在完成时搭配的时间状语
1. since + 时间点
a. I’ve worked in thiss company since 1980
b. I’ve worked in this company since I left school. (从句中一般过去时)
2. for + 时间段
a. I’ve worked in this company for three years.
b. Great changes have taken place in Beijing for the past few years.
3. 到目前为止：until now, up until now, up to now, up till now, so far.
a. We have up until now failed to take any action to decide on a common language that would further communication between nations.
4. 在最近几世纪/年/月以来：in the past few years, over the past few years, during the last three months, for the last few centuries, through centuries, throughout history.
a. Throughout history man has had to accept the fact that all living things must die, for the very nature of life includes death.
b. Through centuries the bizarre anticss of sleepwalkers have puzzled police, perplexed scientists anad fascinated writers.
现在完成时(二)：过去发生但与现在仍有联系的动作或状态
a. He has broken his leg. 他现在还在医院，所以不能和同学一起郊游。
b. He broke this leg. 退摔断过，单纯表示一种过去的经历，但现在腿已经好了。
c. You should have put the milk into icebox; I expect it has become undrinkable by now.
牛奶变质是过去某一时刻的动作，但其影响延续到现在。现在牛奶已经不能喝了。
第二种现在完成时使用技巧。
1. 不与一段时间的时间状语连用：常见 come, go, leave, kill, die, lose, buy, start, give, marry
he has left his hometown for 3 years.
改正：
a. He left this hometown 3 years ago.
b. It’s 3 years since he left this home town.
c. He hasn’t come back since he left his hometown 3 years ago.
d. He has been away from his home town for 3 years.
2. 终止性动词的完成时句子若用否定，表示尚未发生的事情，则可以为一种状态，从而表示延续。
a. I haven’t seen a film for weeks.
b. I haven’t heard form my girlfriends since I came to America
c. I haven’t bought a pair of shoes for a year.
3. 与不确定时间的时间状语连用
这种完成时，可以同一些表示不确定的时间状语连用：already, yet, lately, often, just, never
a. A: would you like something to eat?
B: No, thanks. I’ve just had dinner.
b. The leading expert on sleep in America claims that he has never seen a sleepwalker.
c. Has it stopped raining yet?
d. He has already arrived.
f. I have often thought that it would be perfect if we could fly without any aid.
4. 具有新闻性质：表示最近才发生的动作，提供新消息。有新闻性质
a. The President has been assassinated.
b. He can’t go on holiday because he has broken his leg.
强调的时间内容，而不算是发生的过去具体时间。
通常的日常对话，以现在完成时开始问答。过去时间咋唉说话人的脑子中已经确定了，则继续用一般过去时。
c. I hear that famous Chinese comedian has died.
Really? When did she die? She was dead late last night.
现在完成时(三)：表示到目前为止的一个时间段内重复发生的动作。
For more than eighty years, scientists have argued over whehter life exists on the planet Mars.
We have taken three tests so far this week.
其他现在完成时的结构
1. This/ That/ It is + 序数词 + 名词 + that + 现在完成时
a. It is the third thime that I’ve come to Beijing.
b. It is the fifth time that someone has knocked at my door.
c. This is the thenth cup of coffee that I’ve drunk this evening.
2. This/ That/ It is + 最高等或only修饰名词 + 现在完成时
a. This is the most interesting movie that I’ve ever seen
b. This is the best wine I have ever drunk
c. This is the hardest job I have ever had.
3. 如果是It was the second/ best… that 后面要用过去完成时
a. It was the fifth time that someone had knocked at my door that night.
总结：一直在持续； 重复发生；影响现状
现在完成时与一般过去时比较
不同时态，表明了说话的时间不同。
a. I haven’t seen him this morning.
b. I didn’t see him this morning.
a. 句用了现在完成时，而完成时生死要与现在发生联系的。所以a说话的时间是this morning
b. 句用的是一般过去时，说明this morning已经成为了过去，所以b说话时间是今早后
c. I have called thim three times this morning.
d. I called thim three times this morning.
c. 表示到现在为止的一个是时间段内重复的动作。所以c说话时间是this morning
d. 过去时，和现在没有什么联系，所以说话时间是今早后
延续性动词的两种时态区别
a. He lives in Beijing. He has lived here for 3 years. (可能还继续住在这里)
b. He lived in Beijing for 3 years and then emigrated to America (曾经住过，已经搬走了)
过去完成时：过去某时刻之前就开始的动作；
(1)该过去时刻仍然在继续，或该过去时刻刚刚停止
(2)在该过去时刻之前的某一时刻已经停止的动作做
(3)在该过去时刻之前一段时间内重复的动作
(1)
a. I had stayed in America for two years when he moved here.
b. I had lived in 兵庫 for one and a half years when I came to Aizu.
有上下文表示持续过去这一时刻刚刚停止
c. I had waited for her for two hours in susch a severe winter when she eventually turned up
d. There had been fifty colleges in our city up till 1993.
(2)
a. She had made everything ready before I came.
b. Her baby had fallen asleep when she went into the room.
c. Before John got home, Mary had gone to bed.
d. I had just poured myself a cup of tea when the phone rang. When I came back from answering it, the cup was empty. Somebody had drunk the tea or thrown it away.
(3)
a. I had written her 100 letters when she finally promised to marry me.
b. I had proposed to her five times, but she still refused to marry me.
过去完成时的其他用法
1. intend, mean, hope, want, plan, suppose, expect, think, propose, wish
动词的过去完成时，可以表示过去未能时间的计划，设想，意图或希望等
a. I had planned to go shopping with you but my mother came to see me just when I was about to go.
b. She had hoped that he would come to date her, but he didn’t show up.
c. I had intended to see you, but I was busy.
d. They had hoped to see you off at the airport, but they got there too late.
2. 用在It was the + 序数词 或最高级 that 句中。
a. Last week I attended an international conference and saw Mr. Machine. It was the third time that I had met him.
一把拿过去时与过去完成时的比较
1. 两个或以上相继发生的动作，用and 或 but 按动作发生的先后顺序连接，此时要用一般过去时。 过去完成时则强调主语在过去某一时刻回顾更早的动作，具体来说。当我们在讨论过去某一事件时，想到了在这之前已经发生的某事，这时用过去完成时。
a. He opened the door and entered, but found nobody.
b. He served in the army for ten years; then retired and married. His children are now at school.
c. When I had written my letters I did some gardening.
d. When I wrote him a letter, he came at once.
e. When the singer had sung her song, she sat down.如果说when the singer sang her song, she sat down.给中一种印象，这位歌手喜欢坐着唱歌。
将来完成时：站在将来某一时间来谈某一个动作的完成情况
动作开始的时间可以是过去，现在，未来。但并不重要，说话人强调的是他们一共有5门
a. We started our exam yesterday and we will have taken five exams by next Friday.
b. We have started our exam today and we will have taken five exams by next Friday.
c. We will start our exam tomorrow and we will have taken five exams by next Friday.
1. 同现在完成时第一种用法的将来完成时
a. I will have taught English in New Oriental School for five years by the end of next month.
b. I will have learned 8000 words by the end of next year.
c. I will have waited for her for two hourss when she arrives at 2 o’clock this afternoon.
2. 同现在完成时第二种用法的将来完成时：对将来有影响
a. We will have finished our exam by the end of next week.
b. By the year 2050, scientists probably will have discovered a cure for cancer.
c. I will graduate in July. I will see you in September. By the time I see you, I will have graduated.
d. I will have finished my homework by the time I go out on a date tonight.
3. 同现在完成时第二种用法的将来完成时：重复发生。
a. By five o’ clock this afternoon the spaceship will have traveled eleven times round the world.
完成时的三种思维用法
1. 延续到现在的动作或状态，可能继续延续，也可能到现在为止。
2. 过去发生但与现在仍有联系的动作或状态。对现在有影响。
3. 到目前为止的一个时间段内重复发的动作。
4.不同时间的完成时本质上是一样的。只是说话人的立足时间不同。
● Sorry I’m late. The car broke down on my way here.
● Yesterday I had a phone call from Clint. I was very surprised. I had written to him many times but he had never replied to my letters.
● The man sitting next to me on the plane was very nervous. It was his first flight. He had never flown before.
● Last spring I went to France. It was the first time that I had been there.
● Look! Somebody has spilt milk on the carpet. Well, it wasn’t me. I didn’t do it. I wonder who it was then.
● I lost my key, so I couldn’t get into my house. But now I have found it.
● He has been in the army for five years.
● I’ve already had lunch.
英语学习-语法系列github仓库，欢迎收藏star
参考文章:
参考链接
1.英语语法-基本语法
2.英语语法-句子类型
3.英语语法-状语从句
4.英语语法-形容词adjective
5.英语语法-限定词2
6.英语语法-限定词1
7.英语语法-完成进行时
8.英语语法-人称代词
