條件句中的虛擬語氣

　　　1. 條件句中虛擬語氣的形式

　　從句中提出一種與客觀現(xiàn)實(shí)不相符或根本不可能存在的條件，主句會(huì)產(chǎn)生的一種不可能獲得的結(jié)果。條件句中的虛擬語氣根據(jù)不同的時(shí)間有三種不同的形式。

　　時(shí)間 從句謂語形式 主句謂語形式

　　將來動(dòng)詞過去式(be用were)

　　should + 動(dòng)詞原形

　　were to + 動(dòng)詞原形

　　would / should / might / could + 動(dòng)詞原形

　　現(xiàn)在動(dòng)詞過去式(be 用 were)would / should / might / could + 動(dòng)詞原形

　　過去had +動(dòng)詞過去分詞would / should / might / could have + 動(dòng)詞過去分詞

　　2. 條件句中的虛擬語氣的舉例

　　(1) 將來時(shí)的條件句中的虛擬語氣。如：

　　If he should go to Qing Hua University, he would make full use of his time. 如果他要上清華大學(xué)的話，他就會(huì)充分利用他的時(shí)間了。

　　If he were to come here, he would tell us about it. 如果他要來的話，他會(huì)通知我們一聲。

　　(2) 現(xiàn)在時(shí)的條件句中的虛擬語氣。如：

　　If he were free, he would help us. 要是他有空的話，它會(huì)幫助我們的。

　　If he studied at this school, he would know you well. 如果他在這所學(xué)校學(xué)習(xí)的話，它會(huì)對(duì)你很熟悉。

　　(3) 過去時(shí)的條件句中的虛擬語氣。如：

　　If I had seen the film, I would have told you about it. 我如果看過這場(chǎng)電影，我會(huì)把電影內(nèi)容告訴你了。

　　If I had got there earlier, I would have met Mr. Li. 如果我早點(diǎn)到那兒，我就會(huì)會(huì)到了李先生。

　3. 運(yùn)用條件句中的虛擬語氣時(shí)，須注意的幾個(gè)問題

　　(1) 當(dāng)從句的主語為第三人稱單數(shù)時(shí)，謂語動(dòng)詞若是系動(dòng)詞be時(shí)，可用 was 代替 were。但在倒裝虛擬結(jié)構(gòu)及 if I were you, as it were 中，只能用 were。如：

　　Were I ten years younger, I would study abroad. 要是我還年輕十歲的話，我會(huì)去國外學(xué)習(xí)。

　　If I were you, I would try my best to grasp the chance. 要是我是你的話，我要盡力抓住這次機(jī)會(huì)。

　　(2) 有時(shí)，虛擬條件句中，主、從句的動(dòng)作若不是同時(shí)發(fā)生時(shí)，須區(qū)別對(duì)待。

　?、購木涞膭?dòng)作與過去事實(shí)相反，而主句的動(dòng)作與現(xiàn)在或現(xiàn)在正在發(fā)生的事實(shí)不符。如：

　　If I had worked hard at school, I would be an engineer, too. 如果我在學(xué)校學(xué)習(xí)刻苦的話，我現(xiàn)在也會(huì)使工程師了

　　If they had informed us, we would not come here now. 如果他們通知過我們的話，我們現(xiàn)在就不會(huì)來這里了。

　?、趶木涞膭?dòng)作與現(xiàn)在事實(shí)相反，而主句的動(dòng)作與過去事實(shí)不符。如：

　　If he were free today, we would have sent him to Beijing. 如果他今天有空的話，我們會(huì)已經(jīng)派他去北京了。

　　If he knew her, he would have greeted her. 要是他認(rèn)識(shí)她的話，他肯定會(huì)去問候她了。

　?、蹚木涞膭?dòng)作與過去發(fā)生的情況相反，而主句的動(dòng)作與現(xiàn)在正在發(fā)生的情況相反。如：

　　If it had not been raining too much, the crops would be growing much better. 如果天不下太多的雨的話，莊家會(huì)長得更好。

　　If he had been working hard, he would be working in the office now. 要是他工作一直努力的話，他現(xiàn)在已進(jìn)了辦公室了。

　　(3) 當(dāng)虛擬條件句的謂語動(dòng)詞含有 were, should, had 時(shí)，if 可省略，而將 were, should, had等詞置于句首。如：

　　Should he agree to go there, we would send him there. 要是他答應(yīng)去的話，我們就派他去。

　　Were she here, she would agree with us. 如果她在這兒的話，她會(huì)同意我們的。

　　Had he learnt about computers, we would have hired him to work here. 如果她懂一些電腦知識(shí)的話，我們會(huì)已經(jīng)聘用他來這里工作了(from www.yygrammar.com)。

　　(4) 有時(shí)，句子沒有直接給出假設(shè)情況的條件，而須通過上下文或其他方式來判斷。如：

　　I would have come to see you, but I was too busy. 我本該來看你了，然而我太忙了。

　　But for his help, we would be working now. 要不是他的幫助，我們還會(huì)在工作呢。

　　Without your instruction, I would not have made such great progress. 要是沒有你的指導(dǎo)，我不會(huì)取得如此大的進(jìn)步。

　　(5) 有時(shí)，虛擬條件句中，主、從句可以省略其中的一個(gè)，來表示說話人的一種強(qiáng)烈的感情。

　?、偈÷詮木?/p>

　　He would have finished it. 他本該完成了。

　　You could have passed this exam. 你應(yīng)該會(huì)通過這次考試了。

　　②省略主句

　　If I were at home now. 要是我現(xiàn)在在家里該多好啊。

　　If only I had got it. 要是我得到它了該多好啊。