■本站特約作者 陳根花

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(yǔ)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(yǔ)形式	主句謂語(yǔ)形式
將來(lái)	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(yǔ)氣的舉例

(1) 將來(lái)時(shí)的條件句中的虛擬語(yǔ)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(lái)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(yǔ)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(yǔ)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(yǔ)氣時(shí)，須注意的幾個(gè)問題

(1) 當(dāng)從句的主語(yǔ)為第三人稱單數(shù)時(shí)，謂語(yǔ)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(guó)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)。