最新if和unless區(qū)別和練習(xí)資料

1、 精品文檔chapter 1 語法if 和 unless 引導(dǎo)的條件狀語從句我們用 if 引導(dǎo)的條件狀語從句來討論可能的條件以及該條件成立時可能的結(jié)果。一. 學(xué)習(xí) if 引導(dǎo)的條件狀語從句的用法，我們可先從如下的口訣入手：if 條件句不一般，幾個要點記心間；條件句，放在前，逗號要句中間條件句表可能，主句多用將來時；條件句表事實，主句常用現(xiàn)在時。we can walk there if we cant find a bus. 如果我們找不到公車，也能走路去那里主句if it rains tomorrow, we will not go to the zoo. 如果明天下雨，我們就不去動物園條件狀

2、語從句 主句what will you go if you find someone in danger?主句 條件狀語從句條件狀語從句如果你發(fā)現(xiàn)某人有危險，你會怎么做？if 條件句有不同的類型，簡述如下：1. 用 if 條件句表達(dá)客觀真理或普通現(xiàn)象if 條件句用于表達(dá)客觀真理或普通現(xiàn)象時，主，從句時態(tài)均用一般現(xiàn)在時，如：eg. if you freeze water, it turns into ice.a fish dies if you take it out of water.2. 用 if 條件句表示將來可能發(fā)生的事情在表示將來可能發(fā)生的事情的 if 條件句中，主句用一般將來時，而

3、if 從句用一般現(xiàn)在時表示將來的時間，即主將從現(xiàn)eg. if i like the house, i will buy it. 如果我喜歡這房子，我就會把它買下i will tell her if i see her. 如果我見到她，我就會告訴她。主句中的 will 也可以用情態(tài)動詞 can, may 或 might 等代替。如：eg. if they are friendly，i might invite them to the party. 如果他們很友善，我可能會請他們?nèi)⒓泳蹠f we hurry now, we can stop for coffee later. 如果我們現(xiàn)在抓緊

4、時間，就可以稍后去喝咖啡精品文檔 精品文檔注意：在條件句中，主句部分只能使用動詞 will 的一般將來時，不能使用 be going to 的結(jié)構(gòu)二. unless 的條件句表示在特定條件下，才決定做或不做一件事，中文用的連接詞一般是“除非”和“否則”。如：除非刮臺風(fēng)，否則演唱會將如期進(jìn)行。在英語中，我們可以用unless 表達(dá)這個意思，相當(dāng)于 if not。以這個句子為例：the concert will be held as schedule unless there is a typhoon.= the concert will be held as schedule if there

5、is not a typhoonshe will keep on singing unless she is told to stop. 她會一直唱下去，除非有人叫她停止= she will keep on singing if she is not told to stop也可以用 or(否則) 來做同義句轉(zhuǎn)換unless you listen carefully, you wont know the answer.= if you dont listen carefully, you wont know the answer.= you should listen carefully, o

6、r you wont know the answer.深圳中考題：1. if i _ his phone number, i will tell you.a. find2. we will go camping if it _ tomorrow.a. wont rain b. didnt rain c. doesnt rain3. im waiting for my friend. if he _, i _ swimming alone.b. foundc. will findd. have foundd. isnt raininga. doesnt come; will gob. wont

7、come; will god. dont come; will goc.will come; wont go4. _ you go to the supermarket at 7 p.m, you can buy a lot of cheap food.a. if b. unless c. whether d. when5. i wont get to the party on time _ i catch the first train tomorrow morning.a. ifb. unlessc. whetherd. when6. -shall we go on a picnic th

8、is weekend?-good idea! unless it _.a. rainsb. doesnt rainc. raind. wont rain精品文檔 精品文檔7. -can i change the jacket for another one _ it doesnt fit me well?- of course.a. unlessb. ifc. thathe works hard on it.d howeverd. though8. nobody can learn maths wella if b unless c thought9. if fisha are taking,

9、 wontc are being taken, willaway from water, theydie.b are taken, willd take, wont10. each student can ask teachers for help if hehow to work out the problem.d doesnt knowa will knowb wont knowc dont know練習(xí):a woman should never be seen eating or drinking, unless it be lobster salad andchampagne, the

10、 only true feminine and becoming viands.lord byroni dont feel right unless i have a sport to play or at least a way to work up a sweat.hank aaronno great poetry, of whatever kind, is conceivable unless the subject has becomeintegrated with the poets mind and mood.lascelles abercrombieim not going to

11、 just say nice things about everybody unless i mean it.abrahamf. murrayunless youre willing to have a go, fail miserably, and have another go, success wonthappen. phillip adams1. if i _ you, i _ very happy.a. were, would bec. were, shall beb. am, shall bed. am, would be2. if he had not lost his mone

12、y, he _ the piano last week.a. would buyb. had boughtd. boughtc. could have bought3. _i known it, i should have told him.精品文檔 精品文檔a. haveb. had c. having d. if4. _ the clouds, you would find the airplane in the sky easily.a. were it not forc. if it were notb. if it had not been ford. had it not been

13、 for5. if i had known that, i _ so.a. wouldnt doc. didnt dob. wont dod. wouldnt have done6. if it _ so hard, wed go to town.a. isnt raining b. werent rainingc. doesnt raind. isnt going to rain1.答案 a 2 答案 c 3.答案 b 4.答案 a 5.答案 d 6.答案 b7. he _ you if you _ to see him that afternoon.a. might tell, were

14、goingb. told, were goingc. might have told, had goned. should tell, went8. if you had started sooner, you _ there.a. may have gotc. shall have gotb. might have gotd. must have got9. if we were to be 2oo years old, we _ everything.a. will changeb. can changed. shall changec. could change10. i dont th

15、ink that i shall fail, but if i _ i would try again.a. failb. would faild. had failedc. should fail11. if you _ to see mary, what would you tell her?a. areb. will be going精品文檔 精品文檔c. mustd. were12. if the train leaves at half past ten, there _ no time to lose.a. would b. is c. will d. has7.答案 c 8.答案

16、 b 9.答案 c 10.答案 c 11.答案 d 12.答案 bunless“除非，如果不”(=ifnot)例句 wi shall go tomorrow unless it rains. 如果不下雨，我明天去。shall tom go and play football?not unless he has finished his homework. 除非他完成作業(yè)，否則不能出去。i wont go unless he comes to invite me himself.w 除非他本人來邀請我，不然我是不會去的。i wont attend his birthday party unless invited (=unless i am invited). 除非被邀請，否則我不去參加的生日晚會。1. the men will have to wait all day _ the doctor works faster.（2001 北京春季）a. i