新東方名師：大學(xué)英語四級考試語法提綱

　　I should have practiced more (than I did)! (完成)

　　我應(yīng)該多多練習(xí)!(言下之意，現(xiàn)在我練習(xí)得不多。)

　　I shouldn't dream away my time too much! (完成的否定)

　　(actually I did dream away my time too much!)

　　It shouldn't have been leaking for such a long time! (完成進(jìn)行)

　　I may/might/could have finished! (完成)

　　一些常見的句型中，就會出現(xiàn)這種虛擬語氣，而處于從句之中，should 常常被省略掉

　　o suggest, advise, propose, recommend, plan;

　　o demand, order, direct, arrange, command, decide;

　　o require, request;

　　o think, expect, believe, insist, suspect.

　　由于他們的含義中包含"建議，假設(shè)，應(yīng)該"這類的含義，所以，由他們引起的從句中，就會包含有should+原型時(shí)態(tài)構(gòu)成的虛擬語氣。

　　這些動詞(以及他們的名次形式，分詞形式)引起的從句還有其他的變形：

　　主語從句，表語從句，同位語從句

　　It's suggested that…

　　My suggestion is that…

　　The only suggestion that...

　　The only suggestion I can give you now is that…

　　一些形容詞引起的表語從句中，也會有同樣的情況

　　important; necessary; essential

　　It's natural ; strange; incredible that

　　a pity; a shame; no wonder

　　? 由lest, for fear that, in case 引起的從句中多使用should

　　v 表達(dá)與事實(shí)相反

　　1. 與現(xiàn)在相反：使用[過去時(shí)]：

　　I wish I were not here! (一般現(xiàn)在à一般過去)

　　Suppose we were not here.

　　He loved me as if I were his own son. (一般現(xiàn)在à一般過去)

　　Hope I weren't always losing things! (現(xiàn)在進(jìn)行à過去進(jìn)行)

　　If only/If I hadn't been there! (現(xiàn)在完成à過去完成)

　　What if I hadn't been waiting right here! (現(xiàn)在完成進(jìn)行à過去完成進(jìn)行)

　　�？季湫停篒t's (high) time (that)…; would rather (that)…

　　這兩個(gè)從句，只能表達(dá)對現(xiàn)在的看法，所以，從句中只有一般過去時(shí)。

　　2. 與過去相反：過去完成時(shí);

　　How nice it is if I had past the test!

　　How nice it is if I had slept a little more this morning!