现在完成时课件.ppt

现在完成时：
表示过去发生或已经完成的某一动作对现在造成的影响或结果，或从过去开始一直延续到现在的动作或保存的状态。
结构： 主语+ have / has + 动词的过去分词
一般疑问句： have / has … ?
Yes, I have. No, I haven’t.
Yes, she has. No, she hasn’t.
现在完成时动词构成
have /has + v 过去分词
助动词
否定
haven’t
hasn’t
疑问
Have you…?
Has he…?
现在完成时
。和already，never,ever,just,before,yet等状语连用。
，持续到现在的动作或状态，
常与for或since引起的一段时间状语连用。
have breakfast
I have just had my breakfast.
(现在我不饿)
I’m not hungry now
moved here
in 2013
I still live here
I have lived here for three years.
I have lived here since 2013/three years ago.
now
past
现在完成时：表示过去发生或已经完成的某一动作对现在造成的影响或结果，或从过去开始一直延续到现在的动作或保存的状态。
一般过去时：一般过去时只表示过去的动作或状态，和现在不发生关系（即动作或状态在现在已经结束），它可以和表示过去的时间状语连用。
现在完成时与一般过去时的区别：
have / has + V过去分词
注意:
现在完成连用时不能和明确指出时间的状语
(如: yesterday, last, year, in 1976, two days
ago, just now, when she came in 等)连用，
但可以和不明确指出时间的状语(如: already,
yet, ever, never,before, once, twice, recently, so
far ,in the last /past years等） 连用 。

I have cleaned my room. (My room is clean now.)
我已经打扫过我的房间了。
I cleaned my room last week. (I did it in the past.)
我上周打扫了我的房间。
H has gone to Dehui. (He went to Dehui and
he is not here now.) 爸爸已经去德惠了。
They have bought a dictionary. (They bought
a dictionary and they have it now.)
他们买了一本字典。
( 1).for+表示一段时间的短语
( 2).since+表示过去时间点的词语
( 3).since+表示过去时间的时间状语从句
have been a teacher ______ a year.
He has been at this school _______ 1992.
We have learned 1,000 English words _______ we came to this school.
for
since
since
现在完成时句中常见的时间状语
表示从过去一直持续到现在, 不能是具体
的过去时间。
二者可以转换
for + 一段时间 = since + 一段时间 + ago
He has been here for five weeks.
= He has been here since five weeks ago.
他到这儿已经有五个星期了。
since,for引出的时间状语用 how long提问。
—How long have you had this book?
这本书你买多久了?
—For a week./Since a week ago.
买一周了。