高考英語(yǔ)關(guān)鍵知識(shí)點(diǎn)(2)
高考英語(yǔ)關(guān)鍵知識(shí)點(diǎn)
高考英語(yǔ)關(guān)鍵知識(shí)點(diǎn)：祈使句
1. 祈使句的概念
表示請(qǐng)求、命令、建議、祝愿、邀請(qǐng)或要求的句子叫祈使句。用于祈使句句首的動(dòng)詞總是用原形，不能用其他形式。如：
Shut the door! 把門關(guān)上!
Have a cup of coffee! 喝杯咖啡吧!
Let them go by train. 叫他們坐火車去吧。
祈使句的主語(yǔ)通常為第二人稱(you)，但一般都被省略，只有在特殊的情況下才把主語(yǔ)(you)補(bǔ)充出來(lái)。如：
You be quiet! 你安靜!
You go and tell him, Chris. 克立斯，你去告訴他。
You wait here for a moment. 你在這兒等一會(huì)兒。
有時(shí)祈使句的主語(yǔ)也可以是everybody, somebody, anybody, nobody等不定代詞。如：
Stand up, everybody! 全體起立!
Nobody move. 任何人都不許動(dòng)。
2. 祈使句表示強(qiáng)調(diào)
為了加強(qiáng)祈使句的語(yǔ)氣，我們通常是在祈使句的動(dòng)詞原形前加上助動(dòng)詞do，此時(shí)通常譯為“一定”“務(wù)必”等。如：
Do be careful. 務(wù)必要小心。
Do have some more tea. 一定再喝點(diǎn)茶。
Do let me go. 一定讓我去。
副詞never和always有時(shí)可用于祈使句句首，表示強(qiáng)調(diào)。如：
Never do that again. 再不要這樣做了。
Always look in the mirror before starting to drive. 一定要先看看反光鏡再開(kāi)車。
3. 祈使句的否定式
構(gòu)成祈使句否定式的方法很簡(jiǎn)單，那就是在動(dòng)詞原形前加don’t——不管祈使句所用的動(dòng)詞為什么性質(zhì)動(dòng)詞，情況都是一樣。如：
Open the window. 把窗戶打開(kāi)。
→Don’t open the window. 別把窗戶打開(kāi)。
Come next Monday. 下周星期一來(lái)。
→Don’t come next Monday. 下周星期一別來(lái)。
對(duì)于以let us或let’s開(kāi)頭的祈使句，其否定式通常是在不定式之前放一個(gè)not。如：
Let’s tell him the truth. 我們把實(shí)情告訴他吧。
→Let’s not tell him the truth. 我們不要把實(shí)情告訴他。
但在日?？谡Z(yǔ)中，我們也可以把don’t放在let’s之前。如：
Let’s don’t tell him the truth. 我們不要把實(shí)情告訴他)
4. 祈使句與連用please
為了使祈使句的語(yǔ)氣變得委婉，我們可以在祈使句的句首或句末加上please——若加在句首，其后不用逗號(hào);若加在句末，則通常會(huì)在please前加一個(gè)逗號(hào)。如：
Step this way, please. 請(qǐng)這邊走。
Please type your letter. 請(qǐng)把你的信打出來(lái)。
Open the window, please. 請(qǐng)把窗戶打開(kāi)。
如果是否定祈使句，則通常將please加在don’t之前。如：
Please don’t get angry. 請(qǐng)不要生氣。
Please don’t telephone before 8 a. m. 早8點(diǎn)以前請(qǐng)不要打電話。
5. 祈使句的時(shí)間概念
祈使句所表示的時(shí)間總是指將來(lái)，所以與它連用的句子原則上要用將來(lái)時(shí)態(tài)來(lái)與它呼應(yīng)。如：
Give me a hand, will you? 幫我一個(gè)忙，好嗎?
由于give me a hand表示隱含將來(lái)意義，所以句中的will you 不能改為do you。
Try again and you will succeed. 你再試就會(huì)成功。
由于句中的try again隱含將來(lái)意義，所以句中用了you will succeed，而不是you succeed。
Don’t do that again or you’ll be in trouble. 別再干那個(gè)了，否則你會(huì)有麻煩。
句中的don’t do that again指的是以后不要再干那事了，由于隱含有將來(lái)意義，所所以句中用了you’ll be in trouble，而沒(méi)有用you are in trouble。
6. 祈使句的省略
一般說(shuō)來(lái)，祈使句總是要以動(dòng)詞原形開(kāi)頭，但是，在某些特殊情況下，我們可以只用一個(gè)詞或短語(yǔ)來(lái)表示祈使句的意義。如：
Just a few please. 請(qǐng)給幾個(gè)就行了。
A little more slowly please. 再慢一點(diǎn)。
A pound of butter. 給我一磅黃油。
Two teas and four coffees, please. 請(qǐng)來(lái)兩杯茶和四杯咖啡。
高考英語(yǔ)關(guān)鍵知識(shí)點(diǎn)：重要句型
1. be doing/ be about to do/ had done...when..(when這時(shí)強(qiáng)調(diào)一個(gè)動(dòng)作的突然發(fā)生)
1). I was walking along the river， when I heard a drowning boy cry for help.
2). I was about to leave when it began to rain.
3). I had just finished my test paper when the bell rang， announcing the exam was over.
2. It was (not ) + 時(shí)間段+before +一般過(guò)去時(shí)過(guò)了一段時(shí)間就……..
It will (not )be+ 時(shí)間段+before +一般現(xiàn)在時(shí)要過(guò)一段時(shí)間才會(huì)…
It is/ has been +時(shí)間段+ since…..
It was +點(diǎn)時(shí)間+ when…..
It was +時(shí)間狀語(yǔ)+ that …..(強(qiáng)調(diào)句)
1). It was not long before he sensed the danger of the position.不久他就意識(shí)到他處境危險(xiǎn)
2). It will be half a year before you graduate from the school. 還有半年你才從這個(gè)學(xué)校畢業(yè)
3). It is 3 years since he worked here.=he left here.(since從句中的謂語(yǔ)動(dòng)詞若是延續(xù)性動(dòng)詞，奇速英語(yǔ)提醒要從這個(gè)動(dòng)作結(jié)束的時(shí)候算起)
4). It was 3 o’clock when they received the telephone.
5) It was at 3 o’clock that they received the telephone.
3. once…..一旦…..，表示時(shí)間和條件
1)Once you understand what the teacher explained， you will have no difficulty doing the work.
2). Once you have decided to do something， you should finish it and do it well.
4. The +比較級(jí)…….，the +比較級(jí)……..越……，越……
1) The more books you read， the more knowledge you will get.
2)The busier he is，the happier he feels.
5. as if/ as though…..(表示與事實(shí)相反，用虛擬;若表示即將成為事實(shí)或有可能成為事實(shí)，則用陳述語(yǔ)氣)
1). He was in great trouble， but he acted as if nothing had happened.
2). Although they just met for the first time， they talked as if they had been friends for many years
3). The clouds are gathering. It looks as if it is going to rain.
6. n. /adj. / adv. / v. + as /though +主語(yǔ)+謂語(yǔ)，盡管……，…….引導(dǎo)讓步狀語(yǔ)從句
1).Child as he is，I already know what career I want to follow.
2). Try as he might，he couldn’t solve the problem.
3). Much as I respect him， I can’t agree with his idea.
7. whether….or….無(wú)論是….還是….
1). Whether the weather is good or bad， they will set off as they planned.
2). Any person，whether young or old， has his own worth.
8.疑問(wèn)詞+ever = no matter +疑問(wèn)詞，引導(dǎo)讓步狀語(yǔ)從句或名詞性從句
1). Whichever(=No matter which) you like， you can take it away .( 讓步狀語(yǔ)從句)
You can take away whichever(=anyone that) you like ( 名詞性從句)
2). Whenever you comes， you will be welcome. ( 讓步狀語(yǔ)從句)
3). Whatever happens，I will support you. ( 讓步狀語(yǔ)從句)
4). Whoever breaks the law， he will certainly be punished. ( 讓步狀語(yǔ)從句)
Whoever breaks the law will certainly be punished. ( 名詞性從句)
5). However great the difficulty is， we can overcome it. ( 讓步狀語(yǔ)從句)
9. as long as/so long as/ providing that/provided that/ supposing that/on condition that 假如…..
1). I will lend you money on condition that you can return it within 3 months.
10. in case that/ in case of…..萬(wàn)一…..，以防…..
1). In case of fire，please dial 119 at once.
2). In case that John comes/ John should come， tell him to wait.
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