I. 要點
表示說的話不是事實,或者是不可能發(fā)生的情況,而是一種愿望、建議或與事實相反的假設(shè)等。一般常用于正式的書面語中。
1、 虛擬語氣的構(gòu)成
情景 條件從句的謂語動詞 主句的謂語動詞
與現(xiàn)在事實相反 動詞過去式 (be要用were) should
+動詞原形
would
與過去事實相反 had +過去分詞 should
+have+過去分詞
would
與將來事實相反 1、動詞過去時
2、should +動詞原形
3、were to +動詞原形 should
+動詞原形
would
注:如果條件從句謂語動詞包含有were或had, should, could有時可將if省去, 但要倒裝。如:
Had you (If you had) invited us, we would have come to your party.
2、 虛擬語氣在各種從句的應(yīng)用
(1) 在主語從句中用來表示驚奇、惋惜、理應(yīng)如此等,其謂語形式是"should(可省) +動詞原形",常用于以下三種句型中。
句型一:It is necessary (important, natural, strange, etc) that…
句型二:It is a pity (a shame, no wonder, etc) that…
句型三:It is suggested (requested, proposed, desired, etc) that…
如: It is strange that he (should) have done that.
It is a pity that he (should) be so careless.
It is requested that we (should) be so careless.
(2) 在賓語從句中用于suggest, propose, move, insist, desire, demand, request, order, command等動詞后的賓語從句中,表間接的命令和建議。其謂語形式是"(should)+動詞原形"。如:
I suggest that we (should) go swimming.
(3) 在表語從句中,表示間接的命令,要求、請求、建議、決定等,主句中的主語通常是suggestion, proposal, request, orders, idea等。從句謂語形式是"(should)+動詞原形"。如:
His suggestion is that we (should) leave at once.
(4) 在同位語從句中,謂語形式是"(should)+動詞原形"。如:
We received order that the work be done at once.
(5) 在It is time that…句型中,其謂語動詞形式是"動詞的過去式"或
"should +動詞原形",should不可省。如:It's time (that) we went ( should go) to school.
II. 例題
例1 We had hoped that he ____ longer.
A stays B have stayed C stayed D would stay
解析:該題正確答案為D。had hoped表示"本希望",同樣用法的動詞還有think, expect等,后面的句子需用虛擬語氣
例2 "Mary wants to see you today".
"I would rather she ____ tomorrow than today."
A comes B came C should come D will come
解析:該題正確答案為B。would rather后面的從句需用虛擬語氣,用動詞過去時表示。www.examw.com
例3 Had she been older, she ____ it better.
A had done B might have done C might do D would do
解析:Had she been older = If she had been old. 故該題正確答案為B。