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疑問句
現(xiàn)在完成時的一般疑問句式是把助動詞have或has提到主語之前。
回答：Yes, … have(has).
No, … haven’t(hasn’t).
否定句：
現(xiàn)在完成時的否定句式是“haven't(hasn't)+過去分詞”。
3. 現(xiàn)在完成時的時間狀語:already, just, yet, since, ever, never;
4. 與一般過去時的區(qū)別：一般過去時是強調(diào)動作在過去發(fā)生，而現(xiàn)在完成時是強調(diào)過去發(fā)生的動作對 現(xiàn)在造成了影響和后果。
5.一般過去時的時間狀語：yesterday, just now, …ago, last week, 2 years ago,in 1980等。
例：
We planted (plant) some flowers in the garden last week.
I have sent (send) the letter.
He has come (come ) back home, he is watching (watch) TV now.
David finished (finish) his homework just now.
The monkeys are full, because we have fed (feed) them.
A: I have lost (lose) my purse!
B. Bad luck! When did you lose (lose) it?
A: I lost (lose) it last night.
與現(xiàn)在完成時連用的幾個副詞：already, just, ever, yet, never
肯定句: already, just
疑問句和否定句: ever, yet, never
yet 常置于句末
already, never, ever just一般置于助動詞have/has之后，過去分詞之前.
例：用 already, just或never, yet完成句子
1) I have been to many big cities, but I have never been to Shanghai.
2) Most of us have already finished our compositions.
3) Have they taken down the old pictures yet ? No, not yet .
4) He has already visited Beijing twice.
5) I have just heard the news. I know it.
7. 現(xiàn)在完成時中的for和since
(1)for + 一段時間(用How long提問)
We have known each other for ten years. 我們相識10年了。
(2)since + 句子/具體時間
since 引導(dǎo)的短語或從句用How long提問
①since+過去一個時間點(具體的年、月、日、鐘點等)。
Tom has eaten nothing since yesterday.
②since + 一段時間+ago
We have been friends since five months ago. 從5個月前起，我們就成了朋友。
③since+從句，表示“自過去某個時間、某件事情以來”，從句時態(tài)：一般過去時。
I have lived here since I left Shanghai.
④It is+一段時間+since從句，表示“自從某件事發(fā)生已有一段時間了”。
It is two years since I left school.
8. 在含for或since引導(dǎo)的時間狀語的現(xiàn)在完成時中，謂語動詞只能用延續(xù)性動詞。非延續(xù)性動詞不能直接和for或since 連用。
leave --- be away die --- be dead
begin/start --- be on finish --- be over
come here --- be here go there --- be there
come back --- be back fall asleep --- be asleep
get to/ arrive/reach --- be (in) leave --- be away from
go (get) out --- be out open sth --- keep sth open
join --- be in+組織機構(gòu)/be a member of+組織機構(gòu)
fall ill --- be ill get up --- be up
catch a cold --- have a cold borrow --- keep
buy --- have get to know --- know
put on---wear
例：
1. The old man died 4 years ago.
The old man has been dead for 4 years.
2. It is 4 years since the old man died.
Four years has passed since the old man died.
3. He joined the Party 2 years ago.
He has been in the Party for 2 years.
4. I bought the book 5 days ago.
I have had the book for 5 days.