來(lái)源:本站原創(chuàng)    點(diǎn)擊率:    發(fā)布: 2013-1-22

武漢新東方英語(yǔ)學(xué)習(xí)，情態(tài)動(dòng)詞的現(xiàn)在完成式的用法

 酷學(xué)酷玩冬令營(yíng)英語(yǔ)學(xué)習(xí)    情態(tài)動(dòng)詞現(xiàn)在完成式主要有兩個(gè)功能：表示已經(jīng)發(fā)生的情況和表示虛擬語(yǔ)氣。在這兩個(gè)方面must/mustn’t,;can/cann’t;need/needn’t;may/mayn’t;might/mightn’t;should/shouldn’t;
ougtht等情態(tài)動(dòng)詞＋完成式表示的意思是有一定區(qū)別的
1．表示已經(jīng)發(fā)生的情況。
1）must have+過(guò)去分詞，表示對(duì)已發(fā)生情況的肯定推測(cè)，譯為“（昨天）一定……”。如：
my pain           apparent the moment i walked into the room, for the first man i met asked sympathetically:” are you feeling all right?”
[a] must be       [b] had been     [c] must have been     [d] had to be
（答案為c）
2）can’t / couldn’t have+過(guò)去分詞，表示對(duì)已發(fā)生情況的否定推測(cè)，譯為“（昨天）一定沒(méi)……”。如：
mary         my letter; otherwise she would have replied before now.
[a] couldn’t have received     [b] ought to have received
[c] has received     [d] shouldn’t have received
（答案為a）
3）may / might have +過(guò)去分詞，表示對(duì)已發(fā)生的事情做不肯定、可能性很小的推測(cè)，或事實(shí)上根本沒(méi)發(fā)生，譯為“也許……”。如：
at florida power’s crystal river plant, a potentially serious leakage of radioactive water may have been unknowingly caused by an electrician.
2．表示虛擬語(yǔ)氣。
1) needn’t have + 過(guò)去分詞，表示做了不必做的事，相當(dāng)于”didn’t need to do”,譯為“其實(shí)沒(méi)必要……”。如：
you needn’t have come over yourself.
as it turned out to be a small house party, we         so formally.
[a] needn’t dress up         [b]did not need have dressed up
[c] did not need dress up     [d] needn’t have dressed up
(沒(méi)有必要穿的那么正式，體現(xiàn)是說(shuō)話者的建議，實(shí)際結(jié)果是否真的穿的很正式?jīng)]有確定，答案為d)
2）should have +過(guò)去分詞，表示應(yīng)該做某事但實(shí)際上未做，譯為“本應(yīng)該……”should not + have過(guò)去分詞表示本不應(yīng)該做某事但實(shí)際上做了，譯為“本不應(yīng)該……”。如：
i regret having left the work unfinished; i should have planned everything ahead carefully.
我本來(lái)應(yīng)該事先認(rèn)真地把每件事情規(guī)劃的很好，但實(shí)際上作者還是沒(méi)有規(guī)劃好，以至工作沒(méi)有完成。
3) ought to have +過(guò)去分詞，表示動(dòng)作按理該發(fā)生了，但實(shí)際上未發(fā)生，譯為“該……”，與should 的完成式含義類似。如：
Ｔhe porter ought to have called the fire-brigade as soon as he saw the fire in the stock, which went up in smoke .
4) could have +過(guò)去分詞，表示過(guò)去本來(lái)可以做但卻未做，譯為“完全可以……”。這點(diǎn)與ought/should/ have +過(guò)去分詞用法相似。如：
what you said is right, but you could have phrased it more tactfully.
5) may/ might have +過(guò)去分詞，表示過(guò)去可以做但實(shí)際未做，譯為“（那樣）也許會(huì)……”。如：
it might have been better to include more punchy statistics and photos of equipment in the introduction to further assist first-time office automation managers.