eg：1. Someone has just turned off the light.
2. I have already finished my homework.
我已经完成了家作。 二.表示从过去某一时刻开始并一直延续到现在的动作 或事情,但动作或事情可能仍在继续。
eg：1. I want to see how much the place changed since I saw it last.
2. I have learnt English for more than ten years.
eg：1. Have you ever been to the Summar Palace?
2. I have never had a car.
四.现在完成时还常与句型 This is the first time…，It’s the first time …连用。
eg：1.This is the first time he has driven a car .
What a boring film！
It’s the most boring film I’ve ever seen.
这是我看过的最令人厌烦的电影。 ＊现在完成时除了上述主要用法之外，还有一些其它用 法，在此不一一讲解，请学生自已学习、掌握。
第一单元已讲解了现在完成时， 在第一册中也已讲解了一般过 去时的主要用法。现将这两种 时态的用法加以区别，以便使 学生更好地掌握，区别两者的 不同用法。
一.现在完成时和一般过去时都是 说过去的事情，但现在完成时注意 的不是事情本身，而是强调事情与 现在保持的某种密切联系（如现在 的结果，影响,一直延续到现在 等）;而一般过去时，则只表示发 生在过去的动作和事情与现在没有 关系。
eg ： 1. He has bought an English-Chinese dictionary.
他已经买了一本英汉字典。 eg：2. He bought an English-Chinese dictionary. 他曾买过一本英汉字典。
第一句用现在完成时时态，意为：“He bought an English-Chinese dictionary. And he still has it” “过去他买 了一本英汉字典，现在他还有这本字典” 。 第二句用过去时只叙述过去他买过一本英汉字典这一 事实，至于现在他是否有这本字典并未强调说明。
eg：1. I saw the film on television yesterday . 但since(自…以来)+某一过去时间或叙述过去事情的 从句总是与现在完成时连用。 eg：1. They have known each other since 1950 . 2. Since he was a child,he has lived in England.
三．常与一般过去时连用的典型的表示过去时间的状语 yesterday(昨天),the other day (前两天),just now(刚才)，
ast +时间 ; etc;
eg: 1. eg: 2. The plane took off ten minutes ago 飞机十分钟前起飞了。 We finished our task last week .
四．常与现在完成时连用的表示到现在为止这段 时间的词．短语或从句: so far (到现在为止)，up to (till,until)now直到现 在，lately（最近）yet ,since+过去时间或叙述过 去事情的从句。 eg：1. The weather has been hot so far this summer
2. I haven’t seen her yet . 我还未见到过她。
五．可与现在完成时连用，也可与一般过去时连用 的时间状语： for +时间 ，this +时间
I have learnt English for three years. 我学英语（到现在）三年了（仍在学）。 2. I learnt English for three years. 我学了三年英语（现在不学了）。 3. I have written two letters this morning 今天上午我写了两封信，(说话时仍是上午)。 4. I wrote two letters this morning . 今天上午我写了两封信，（下午或晚上说的）。 注：表示不确定时间的状语，在句中无其它特定的 过去时间状语时，或无表示过去动作的从句时常与 现在完成时连用。 eg: 1. I have not written to my parents recently. 我最近一直未给父母写信。 2. I have met him many times before. 我以前见过他多次。
表示一个持续了一段时间，刚刚结束或仍在继续进行的 动作。与现在完成时有所有同的是现在完成进行时强调 动作本身或动作的持续性、持久性。
eg：1. We’ve been looking for you everywhere.where have you been?
2. What have you been doing?
3. I’ve been writing a laboratory report.
一.Find the choice : 1.When I was at school,I_______to the library every day. A.go B.was going C.have goneD.wen 2.The new books_______yet. A.haven’t arrived B.has’t arrived C.didn’t arrive D.don’t arrive 3.____you ever_______to shanghai. A.Haven’t arrived B.Hasn’t arrived C.Didn’t arrived D.Have…been
4.He_______his lunch. A.had B.have had C.has had D.ate 5.For years,doctors________millions of patients lives with the help of microscopes. A.saved C.has saved B.have saved D.were saving
6.I was so happy to see John again
last Sunday ,We ______each other
for more than two years. A.haven’t seen B.hadn’t seen
A.have learned C.has learned
B.learned D.were having
7.We ______three lessons this month.
8.I______to Paris several times.
A.went B.have gone
9.Alice _______ in china for ten years. A. has lived B.have lived
10.My uncle ____in this city since
11.By now old Wang
factory for twenty years.
A.have worked C.works B.worked D.has worked
12.Christianity(基督教) has become a worldwide religion(宗教) since it
____almost two years ago. A. begin B.begins C.began D. has begin 13.Shakespeare ____many plays such as Hamlet,and Romeo And Juliet. A.writes B.have written
14.When we lived in phoenix we ____
at Arizona State university.
A.studied C.study B.have studied D.were studying
15.I wrote to my parents three mont
ago but I______to my parents lately. A.haven’t written C.didn’t write B.don’t write D.will not write
16.Li Ming _____to Shanghai.He will be back next month. A.went B.have gone
17.She ____an actress for some time . A.was B.being C.is D.has been
18.Professor Chen ____our exams yet. A.didn’t mark B.hasn’tmarked C.will not mark D.haven’t marked
19.He left last year and_____away ever since. A.is B.have been C.was D.has been
20. I_______my task the other day. A.finished B.have finished C.finish D.will finish
二. choose the one that is wrong:
1.I lived in this city since I was a child . 2.I lost my pen, I have to write with a pencil . 3.Hangzhou is the most beautiful city I saw . 4.She has read the book last week .
5.My classmates and I have visited
the memorial hall of chairman Mao
6.My grandmother has lived with us since my grandfather has died six
years ago .
7.After breakfast she takes a walk to buy the morning paper she does this every morning for ten years . 8.It was very hot lately ,but it’s beginning to get a bit cooler . 9.Have you gone to the great wall?Yes,I have ,I went there last Sunday .
三.Fill in the blanks
For the last three days I 1_(work ) hard.When we moved in three days ago ,everything was in a mess ,but now I 2 almost ( finish) the job. Today I 3 (work)since breakfast and 4 (not have )anything to eat . Anne 5 (bring )me a sandwich an hour ago but I 6 (tell) her not to come into the kitchen.
I 7 (never,forget) what 8 (happen)
several years ago when she tried
to help me ,I 9 (hot have )many accidents since then but Anne 10
(often,warn)me to be careful .
she 11 (warn) me again this morning at breakfast time ,
but I 12 (work)for four hours and nothing 13 (go)wrong.Now I
14 (drop) the tin of paint .Has anything like that ever happened to you？
一.1.D 2.A 3.D 4.C 5.B 6.A 7.A8.C 9.D 10.C 11.D 12.C13.C14.A15.A 16.C 17.D 18.B 19.D 20.A
二.1.A 2.A 3.D 4.A 5.B 6.C 7.C 8.A 9.B 10.B 1.lived-have lived2.lost-have lost 3.saw-have seen 4.has read-read
5.have visited-visited 6.has died-died 7.does-has done 8.was-has been 9.gone-been 三.1. have been working 2.have finished 3.have been working 4.have not had 5.brought 6.told7.have never forgotten 8.happened 9.have not had 10.has often warned 11.warned 12.have been working 13.has gone14.have dropped