1、學(xué)必求其心得，業(yè)必貴于專精1 二十四、虛擬語氣1概念虛擬語氣：表示動(dòng)作或狀態(tài)不是客觀存在的事實(shí),而是說話人的主觀愿望、假設(shè)或推測(cè)等。如:if i were you，i should study english 。如果我是你，我就學(xué)英語了.may you succeed! 祝您成功！2虛擬語氣在條件從句中的用法條件句有兩類，一類是真實(shí)條件句，一類是虛擬條件句. 真實(shí)條件句如果假設(shè)的情況是有可能發(fā)生的，就是真實(shí)條件句。在這種真實(shí)條件句中的謂語用陳述語氣 .如：if it doesnt rain tomorrow，we will go to the park。如果明天不下雨，我們就去公園。學(xué)必求其心

2、得，業(yè)必貴于專精2 虛擬條件句如果假設(shè)的情況是過去或現(xiàn)在都不存在的，或?qū)聿淮罂赡馨l(fā)生的，則是虛擬條件句。如：if he had seen you yesterday,he would have asked you about it。如果他昨天見到你，他會(huì)問你這件事的。 （事實(shí)上他昨天沒見到你， 因此也未能問你這件事。） 錯(cuò)綜時(shí)間條件句當(dāng)條件狀語從句表示的行為和主句表示的行為所發(fā)生的時(shí)間不一致時(shí),被稱為錯(cuò)綜時(shí)間條件句，動(dòng)詞的形式要根據(jù)它表示的時(shí)間作出相應(yīng)的調(diào)整。如：if you had followed my advice just now you would be better now。if

3、 you had studied hard before ，you would be a college student now。 if 省略句在條件句中可以省略if， 把 were,had,should 提到句首，變成倒裝句式 .如:if i were at school again ，i would study harder 。were i at school again,i would study harder。 如果我還有上學(xué)的機(jī)會(huì)，我會(huì)更加努力學(xué)習(xí)。if you had come earlier,you would catch the bus.had you come earlier

4、,you would catch the bus.如果你來得早點(diǎn)，你就能趕上公共汽車。學(xué)必求其心得，業(yè)必貴于專精3 if it should rain tomorrow we sould not go climbing.should it rain tomorros iwe would not go climbing.如果明天下雨的話，我們就不能登山去了 . 用介詞代替條件狀語從句常用的介詞有 with,without，but for。如：what would you do with a million dollars？(=if you had a nillion dollars) 如果你有

5、100萬元，你會(huì)做什么？we couldnt have finished the work ahead of time without your help （=if we hadnt got your help) 沒有你的幫助 ,我們不可能提前完成這項(xiàng)工作.without your help we couldnt have finished the work ahead of time。=but for your help,=if it had not been for your help, =had it not been for you help ，沒有你的幫助，我們不可能提前完成這項(xiàng)工作

6、。 含蓄條件句有時(shí)在虛擬語氣中并不總是出現(xiàn)if 引導(dǎo)的條件句 ,而是通過其他手段來代替條件句。如：i was ill that day.otherwise ， would have taken part in the sports meeting 。(副詞）he telephoned to inform me of your birthday，or i would have known nothing about it.( 連詞）學(xué)必求其心得，業(yè)必貴于專精4 a man who stopped drinking water would be dead in about seven days 。（定語從句）i might hawe given you nore help ，but i was too busy