as if 連接的從句,即可表示對(duì)現(xiàn)在、將來時(shí)間的虛擬,又可以是對(duì)過去時(shí)間的虛擬。

基本用法

as if 從句用虛擬語氣，當(dāng)說話人認(rèn)為句子所述的是不真實(shí)的或極少有可能發(fā)生或存在的情況時(shí)。從句虛擬語氣動(dòng)詞時(shí)態(tài)的形式如下：

1、如果從句表示與現(xiàn)在事實(shí)相反，謂語動(dòng)詞用一般過去時(shí)。

2、從句表示與過去事實(shí)相反，謂語動(dòng)詞用“had＋過去分詞”。

3、從句表示與將來事實(shí)相反，謂語動(dòng)詞用“would／could／might＋動(dòng)詞原形”。例如：

You look as if you didn’t care．你看上去好像并不在乎。

He talks about Rome as if he had been there before．他說起羅馬來好像他以前去過羅馬似的。

He opened his mouth as if he would say something．他張開嘴好像要說什么。

兩點(diǎn)說明

1.從句所表示的內(nèi)容若為事實(shí)或可能為事實(shí)，也可用陳述語氣。

It looks as if we'll be late.我們似乎要遲到了。

This meat tastes as if it has already gone bad.這肉吃起來似乎已經(jīng)壞了。

在現(xiàn)代英語中，有時(shí)即使從句內(nèi)容不是事實(shí)，也可用陳述語氣。

I feel as if I'm floating on air.他感到好像漂浮在空中。

The stuffed dog barked as if it is a real one.玩具狗叫起來像真狗。

2.注意It isn't as if的翻譯

It isn't as if…是英語中的固定句式，也可說成 It’s not as though，主要用于表示某個(gè)解釋不正確，意思是“好像不是”“顯然不是”“真不是”等。

It isn't as if he were poor. 他不像窮的樣子（他又不窮）。

It isn’t as if he didn’t recognize me! He just walked straight past me as I stood there. 他不像是沒認(rèn)出我！可是我站在那里他逕直從我跟前走過。

as if 從句的作用

1.在look，seem等系動(dòng)詞后引導(dǎo)表語從句。

She looks as if she were ten years younger.

她看起來好像年輕了十歲。

2.引導(dǎo)方式狀語從句

She loves the boy as if he were he father.

她愛這個(gè)男孩，就好像他是她的父親一樣。

as if還可用于省略句

如果as if引導(dǎo)的從句是“主語+系動(dòng)詞”結(jié)構(gòu)，可省略主語和系動(dòng)詞，這樣as if后就只剩下名詞、不定式、形容詞（短語）、介詞短語或分詞。

He acts as if (he were)a fool.

他做事像個(gè)傻子。

She left the room hurriedly as if (she were)angry.

她匆忙離開房間好像生氣的樣子。