張紅
情態(tài)動(dòng)詞和虛擬語(yǔ)氣是考生高中階段十分重要的一個(gè)語(yǔ)法項(xiàng)目,同時(shí)又是一塊難啃的“硬骨頭”。要想在英語(yǔ)表達(dá)中微妙生動(dòng)地表示出說(shuō)話(huà)人的語(yǔ)氣、心態(tài)或情感,考生必須學(xué)會(huì)準(zhǔn)確地使用情態(tài)動(dòng)詞和虛擬語(yǔ)氣。
情態(tài)動(dòng)詞的考查重點(diǎn)
1. 考查情態(tài)動(dòng)詞在句中使用時(shí)的特點(diǎn)
情態(tài)動(dòng)詞的特點(diǎn):(1)有一定的詞義;(2)不受主語(yǔ)人稱(chēng)和數(shù)的變化影響,但有些情態(tài)動(dòng)詞有過(guò)去式;(3)情態(tài)動(dòng)詞后面跟的動(dòng)詞須用原形,否定式構(gòu)成是在情態(tài)動(dòng)詞后面加 “not”。 其中第3個(gè)特點(diǎn)是近年來(lái)高考考查的重中之重。
【活學(xué)活用】
(2015·全國(guó)新課標(biāo)卷Ⅰ)We must found ways to protect your environment. ( found→find;your→our )
(2016·山東濟(jì)南3月一模)You can found all kinds of delicious food in Beijing, of that the most famous is the roast Beijing duck. ( found→find;that→which )
上面兩道例題,都是為了讓考生掌握“情態(tài)動(dòng)詞后必須接動(dòng)詞原形”的用法。
2. 考查常見(jiàn)情態(tài)動(dòng)詞的基本意義及用法
如今,情態(tài)動(dòng)詞的命題方向主要在常見(jiàn)情態(tài)動(dòng)詞的基本用法上,特別是情態(tài)動(dòng)詞表推測(cè)的用法上,下面是常見(jiàn)情態(tài)動(dòng)詞的基本意義及用法。
(1)can和could
Can可表示能力,could主要指過(guò)去的能力。如:
He can run the 110m hurdle race within 13 seconds.他能在13秒內(nèi)完成110米跨欄。
Could the girl read before she went to school?這個(gè)女孩上學(xué)之前識(shí)字嗎?
Can和could可表示可能性,表推測(cè),常用在否定句及疑問(wèn)句中;如用在陳述句中,則表示客觀(guān)上存在這種可能性。如:
The temperature can fall to –60℃,that is 60℃ below freezing.氣溫可降至-60℃,也就是零下60℃。
If you smoke in the wood, you can start a fire.如果你在林子里吸煙,可能會(huì)引起火災(zāi)。
Can和could也可表示請(qǐng)求, 這時(shí)could語(yǔ)氣更委婉。如:
Can/Could I have a look at your new pen?我可以看一看你的新鋼筆嗎?
He asked whether he could take the book out of the reading-room.他問(wèn)他可不可以把書(shū)帶出閱覽室。
(2)may 和might
May和might可以表推測(cè)(通常表主觀(guān)認(rèn)為), 只用于肯定句。Might 可以指過(guò)去的時(shí)間,也可以指現(xiàn)在的時(shí)間,但語(yǔ)氣更加不肯定。如:
They may/might be having a meeting, but Im not sure.他們有可能在開(kāi)會(huì),不過(guò)我不肯定。
He was afraid they might not agree with him.他擔(dān)心他們可能不同意他的意見(jiàn)。
May和might也常用在疑問(wèn)句中表示許可,表示請(qǐng)求、允許時(shí),might比may的語(yǔ)氣更委婉一些。如:
May/Might I use your computer? 我可以用你的電腦嗎?
(3)must
Must表示推測(cè),意為“一定,肯定”等,只用于肯定句,不能用于否定句和疑問(wèn)句。如:
He must be doing his homework now.他現(xiàn)在一定在做作業(yè)。
Must也可表示義務(wù),意為“必須”(表主觀(guān)意志),否定形式mustnt 表示“禁止,不準(zhǔn)”。如:
We must do everything step by step.我們必須循序漸進(jìn)地做每件事。
You mustnt talk to her like that.你不許那樣對(duì)她說(shuō)話(huà)。
(4)need
Need意為“需要,必要”,用作情態(tài)動(dòng)詞多用在疑問(wèn)句和否定句中,在肯定句中一般作實(shí)義動(dòng)詞。如:
We need to buy a new computer.我們需要買(mǎi)一臺(tái)新電腦。(這時(shí)need只能用作實(shí)義動(dòng)詞)
Its a fine day. You neednt take a raincoat with you.(這時(shí)need可用作情態(tài)動(dòng)詞)
Need they take any books with them? (這時(shí)need可用作情態(tài)動(dòng)詞)
(5)should
Should表示義務(wù)、命令、勸告、建議等, 意為“應(yīng)該”,用于各種人稱(chēng)。如:
You should be polite to your teachers.你對(duì)老師應(yīng)該有禮貌。
You shouldnt waste any time.你不應(yīng)該浪費(fèi)時(shí)間。
(6)will/ would
Will用來(lái)表示意愿和意志,或用在疑問(wèn)句中表請(qǐng)求;would是will的過(guò)去式,表請(qǐng)求時(shí)語(yǔ)氣更委婉。如:
I will do anything for you.我愿為你做任何事。(表意愿)
Will/Would you close the window? Its a bit cold.請(qǐng)你把窗戶(hù)關(guān)上好嗎?有點(diǎn)冷。(表請(qǐng)求)
Every time she was in trouble, she would go to him for help.每次她有麻煩時(shí),她都會(huì)找他幫忙。(表習(xí)慣性動(dòng)作,這里是過(guò)去的情況,所以用would)
3. 考查情態(tài)動(dòng)詞表推測(cè),其中 “情態(tài)動(dòng)詞+have done”是重難點(diǎn)
表推測(cè)在肯定句中一般用must(一定),may/might(可能);否定句中用cant / couldnt(不可能), may not/might not(可能不);疑問(wèn)句中用can/could (能……嗎?)。 如:
It is cold in the room. They must have turned off the heating.屋里很冷,他們肯定把暖氣關(guān)了。
It cant/couldnt be the headmaster, he has gone to America.這不可能是校長(zhǎng),他去美國(guó)了。
He may not/might not know the scientist. 他也許不認(rèn)識(shí)那位科學(xué)家。
Can he be at home now? 他現(xiàn)在可能在家嗎?
對(duì)過(guò)去情況的推測(cè),用“情態(tài)動(dòng)詞 + have +過(guò)去分詞”。
must have done 過(guò)去一定做了某事。
may/might have done 過(guò)去可能做了某事。
cant/couldnt have done 過(guò)去不可能做過(guò)某事。
(2016·浙江卷)George _______ too far. His coffee is still warm.
A. must have gone B. might have gone
C. cant have gone D. neednt have gone
答案:C
解析:?jiǎn)讨巍安豢赡堋弊吆苓h(yuǎn),他的咖啡還是熱的。這里表“不可能已做了某事”,故用cant have done或couldnt have done,選C。
4. 考查特定語(yǔ)境下情態(tài)動(dòng)詞與虛擬語(yǔ)氣相結(jié)合的情況,主要考點(diǎn)有:
should have done 表示過(guò)去本該做某事而沒(méi)做,含“責(zé)備或遺憾”的感情。
neednt have done 表示本沒(méi)有必要做某事而實(shí)際上做了。
could have done 表示本來(lái)能夠做某事而實(shí)際上沒(méi)做到。
should have done 表示過(guò)去本不該做某事而實(shí)際上做了。
(2016·江蘇南京二模)The desk that ________ clean so I could do homework was always surrounded with bowls of bad milk, old magazines and so on.
A. may have been B. would have been
C. must have been D. should have been
答案:D
解析:那張“本應(yīng)”干凈的以便我能做作業(yè)的桌子總是被幾碗變了質(zhì)的牛奶、舊雜志和其他一些東西圍著。這里從語(yǔ)境可知要表達(dá)“本應(yīng)該是而實(shí)際不是”這個(gè)意義,所以選D項(xiàng)should have been。
虛擬語(yǔ)氣的考查重點(diǎn)
虛擬語(yǔ)氣表示說(shuō)話(huà)人的愿望、假設(shè)或要求、建議,而不表示客觀(guān)存在的事實(shí)。虛擬語(yǔ)氣通過(guò)謂語(yǔ)動(dòng)詞的特殊形式來(lái)表示。如今,虛擬語(yǔ)氣的命題方向主要圍繞在非真實(shí)條件句的基本用法上及其基本含義在語(yǔ)境中的靈活應(yīng)用,同時(shí),高考也會(huì)考查虛擬語(yǔ)氣在其他從句中的使用,特別是名詞性從句中“should+動(dòng)詞原形”的用法。
1. 非真實(shí)條件句
(1)If 非真實(shí)條件句的基本用法
與現(xiàn)在事實(shí)相反:If條件狀語(yǔ)從句中用過(guò)去式(did),be動(dòng)詞用were,主句中用would/could/might/should + do(動(dòng)詞原形)。
與過(guò)去事實(shí)相反:If條件狀語(yǔ)從句中用過(guò)去完成式(had done),主句中用would/could/might/should+ have done。
與將來(lái)的事實(shí)可能相反或不可能發(fā)生:If條件狀語(yǔ)從句中用過(guò)去式(did), were to do或should do,主句中用would/could/might/should + do (動(dòng)詞原形)。
這里考查最多的是與過(guò)去事實(shí)相反的虛擬語(yǔ)氣。
【活學(xué)活用】
(2016·北京卷)Why didnt you tell me about your trouble last week?If you ________ me,I could have helped.
A. told B. had told C. were to tell D. would tell
答案:B
解析:你上周為什么不告訴我你的麻煩事呢?如果你告訴了我,我能夠幫忙的。根據(jù)句意,可知是對(duì)過(guò)去的虛擬,故選B。
(2016·浙江卷)Had the governments and scientists not worked together, AIDS-related deaths _______ since their highest in 2005.
A. had not fallen B. would not fall
C. did not fall D. would not have fallen
答案:D
解析:要是政府和科學(xué)家不共同努力,與艾滋病相關(guān)的死亡數(shù)就不會(huì)從2005年的最高峰降低了。從句意看,可知是對(duì)過(guò)去的虛擬,故選D。
(2)含蓄虛擬條件句
這樣的虛擬句不含有if,而是以but for/without/or/otherwise等詞引導(dǎo)句子,主句謂語(yǔ)動(dòng)詞的形式與前面虛擬語(yǔ)氣的用法基本相同。
【活學(xué)活用】
(2016·衡水中學(xué)) With their help and advice, my life would be different. (With → Without)
解析:由句意可知,my life would be different是虛擬語(yǔ)氣,故前面應(yīng)是without引導(dǎo)的含蓄虛擬條件句,不應(yīng)用with。
(3)主句、從句時(shí)間不一致的虛擬條件句
在有些虛擬條件句中,主句、從句的時(shí)間不一致,這時(shí)應(yīng)根據(jù)不同情況分別對(duì)待,即根據(jù)各自的時(shí)間進(jìn)行虛擬。
【活學(xué)活用】
(2016·江蘇卷)If it for his invitation the other day, I should not be here now.
A. had not been B. should not be
C were not to be D. should not have been
答案:A
解析:要不是他前幾天的邀請(qǐng),我現(xiàn)在不應(yīng)該在這兒。由句意及the other day可知,if條件從句是對(duì)過(guò)去的虛擬,主句是對(duì)現(xiàn)在的虛擬,故if條件從句中應(yīng)用過(guò)去完成時(shí),選A。
2. 名詞性從句中“should+動(dòng)詞原形”的虛擬
在含有表示堅(jiān)持、建議、命令、要求等含義的名詞性從句中,從句的謂語(yǔ)動(dòng)詞需用“should+動(dòng)詞原形”,其中should可省略。
【活學(xué)活用】
(2016·全國(guó)新課標(biāo)卷II)Some classmates suggest we can go to places of interest nearby.(can → should或去掉can)
小M提醒:下期關(guān)于從句的語(yǔ)法會(huì)更精彩,請(qǐng)大家不要錯(cuò)過(guò)~~~