if引導(dǎo)的條件狀語(yǔ)從句講解和練習(xí)(答案)

1、條件狀語(yǔ)從句一、 條件狀語(yǔ)從句通常由if（如果）, unless（除非），as long as（只要）引導(dǎo)。例如：If it rains tomorrow, we wont go to the park. 如果明天下雨，我們就不去公園了。 Unless weather stops me, I go for a walk every. 我每天都會(huì)去散步，除非遇上壞天氣。 Our parents will be pleased with our performance as long as we try our best.小試牛刀：1、只要我們竭盡全力，父母就會(huì)滿意我們的表現(xiàn)。 Our paren

2、ts will be pleased with our performance _ _ _ we try our best.2、如果人人為保護(hù)環(huán)境做出貢獻(xiàn)，世界將會(huì)變得更美好。_ _ _ _ _ to protecting the environment, the world will become much more beautiful.二、if引導(dǎo)的條件狀語(yǔ)從句（1）“if從句+祈使句”的句子。其實(shí)，if作為一個(gè)連詞，主句也可以是其他形式的句子。例如：If you want to go, please let me know.If the green light isnt on, wait

3、 for a minute.(2)“祈使句 + and (or)+ 陳述句” 在意思上相當(dāng)于一個(gè)帶有條件狀語(yǔ)從句的復(fù)合句。注意：A. “祈使句 + and + 陳述句”可以轉(zhuǎn)化為if引導(dǎo)的肯定條件狀語(yǔ)從句，而且主語(yǔ)是第二人稱。B. “祈使句 + or + 陳述句”可以轉(zhuǎn)化為if引導(dǎo)的否定條件狀語(yǔ)從句，而且主語(yǔ)是第二人稱。例如：Study hard and you will pass the exam. =If you study hard, you will pass the exam.Hurry up, or youll be late. =If you dont hurry up, you

4、ll be late.考題(2019重慶中考)Work hard，_ you may catch up with your classmates soon.A.orB.butC.andD.yet思路解析：本句是“祈使句and”的句型，句意為“努力學(xué)習(xí)，你會(huì)很快趕上其他同學(xué)的”，and在句中表示承接關(guān)系，所以選C項(xiàng)。答案：C黑色陷阱：本題的陷阱是句型，本句型區(qū)別于“祈使句or”，這個(gè)句型的含義是“，不然的話/否則”。綠色通道：祈使句后面既可以加and，也可以加or，所以要全面分析句意，再作決定。小試牛刀：用if連接下列句子1、Go to bed early and you will have a

5、 good rest. 2、Hurry up, or youll miss the bus.三、if從句及主句具有以下特點(diǎn)：1If從句中用一般現(xiàn)在時(shí)，表示未來(lái)的一種條件，從句中可以加時(shí)間狀語(yǔ)。e.g.If you cant come tomorrow, we can hold the party a little later.明天你如果不能來(lái)，我們可遲一點(diǎn)舉行宴會(huì)。If it doesnt rain tomorrow, well go to the Great Wall. 明天如果不下雨，我們就去長(zhǎng)城。2當(dāng)if表示未來(lái)的條件時(shí)，主句中用一般將來(lái)時(shí)，從句用一般現(xiàn)在時(shí)，即“主將從現(xiàn)”。表示如果某種

6、條件存在，就有可能/不可能發(fā)生什么事情。e.g.If you dont get up early, you will be late for school.你如果不早點(diǎn)起床，上學(xué)就會(huì)遲到。If I play games on it, it will go wrong. 如果我用它玩游戲，它就會(huì)壞掉。3if從句可放在主句前或主句后，從句置于主句前時(shí)，須用逗號(hào)及主句隔開(kāi)，反之則不用逗號(hào)。e.g.If its fine tomorrow, we can go out. 如果明天天氣好，我們就能出去。She will be happy if she joins the party. 如果她參加聚會(huì)她會(huì)

7、很開(kāi)心的。Ill ask the teacher for help if I dont understand. 如果我不懂我會(huì)求助老師的。三注意if引導(dǎo)的條件狀語(yǔ)從句和賓語(yǔ)從句的區(qū)別if可以用來(lái)引導(dǎo)賓語(yǔ)從句也可以用來(lái)引導(dǎo)條件狀語(yǔ)從句，主要是要弄清if引導(dǎo)從句的時(shí)態(tài)。if在引導(dǎo)賓語(yǔ)從句時(shí)，意為“是否”。要根據(jù)實(shí)際情況來(lái)確定時(shí)態(tài)，而if在引導(dǎo)條件狀語(yǔ)從句時(shí)意為“如果，假設(shè)”，要用一般時(shí)代替將來(lái)時(shí)，即“主將從現(xiàn)”。e.g.I want to know if he will come here tomorrow.我想知道他明天是否到這兒來(lái)。（if在上句引導(dǎo)的是賓語(yǔ)從句，從句中有很明顯的表將來(lái)的時(shí)間狀語(yǔ)

8、tomorrow，所以if從句要用一般將來(lái)時(shí)。）e.g.If it rains tomorrow, well put off the sports meeting.如果明天下雨，我們就推遲運(yùn)動(dòng)會(huì)。（if在上句引導(dǎo)的是條件狀語(yǔ)從句，盡管從句中也有表將來(lái)時(shí)的時(shí)間狀語(yǔ)tomorrow，從理論上講也應(yīng)該用一般將來(lái)時(shí)，但是在if引導(dǎo)的條件狀語(yǔ)從句中要用一般現(xiàn)在時(shí)代替一般將來(lái)時(shí)，故從句謂語(yǔ)用rains而不用will rain. ）二、典題分析1、（2019上海）We will have no water to drink we dont protect the earth. A. until B. bef

9、ore C. though D. if 答案D解析 if 引導(dǎo)條件狀語(yǔ)從句，表示 “如果”。意思是如果我們不保護(hù)地球，我們將會(huì)沒(méi)有水喝。2、（2019 重慶）We will plant trees tomorrow, and I dont know Tom will come and join us. A. if B. which C. what D. where答案A解析 if 引導(dǎo)賓語(yǔ)從句，表示 “是否 ”。意思是我們明天將會(huì)去植樹(shù)，但是我不知道Tom會(huì)不會(huì)去。3、Do you know if finished the work? Not yet. If he , he will give

10、 me a call.A. hes, will finish B. hell, finishes C. hes , finishes D. hell , will finish答案C解析問(wèn)句的if 引導(dǎo)賓語(yǔ)從句，表示 “是否 ”，從句要用陳述語(yǔ)序，從答句Not yet.中可以看出從句應(yīng)該用現(xiàn)在完成時(shí)態(tài)，答句的if 引導(dǎo)狀語(yǔ)從句，要遵循主將從現(xiàn)的規(guī)律。練習(xí)一、用if 連接下面的句子：1、 You do not understand the article. Ask your teacher.2、 You want to know more about it. Please call your t

11、eacher.3、Tell him to make a phone call to me.He will come here tomorrow.4、You want to go. Please tell me.5、Look at our website. The camera does not work.二、用所給的提示詞組成一個(gè)if引導(dǎo)的條件狀語(yǔ)從句。1、 be tired, have a rest (Tom)2、 not go to bed early, feel sleepy (you)3、 become unhealthy, not eat vegetables (children)4

12、、 not listen to the teacher, not study well (I )5、 fall behind others in studying, spend too much time on the games (Da Wei)三、單項(xiàng)選擇：1. You are sure to pass the exam _ you study hard.A. if B. thoughC. that D. since2. I'll go to see the film with you_I have time this evening.A. whether B. so C. if

13、D. when3. _ you study harder, you'll never pass the final exam.A. If B. Until C. Unless D. Except4Well stay at home if it _ this afternoon. Arain Brains Cto rain Draining 5We will go to the Great Wall if it _tomorrow. Awont rain Bisnt raining Crained Ddoesnt rain 6 I dont know if he _.He will co

14、me if it _. Acomes; wont rain Bwill come; doesnt rain Ccomes; doesn't rain Dwill come; wont rain 7Do you know what time _？ Athe train leave Bdoes the train leave Cwill the train leave Dthe train leaves 8Do you think if_ an English film tomorrow night？ Ais there Bthere is going to have Cthere is

15、going to be Dwill there be 9Will you please tell me _？ Awhere Pudong Airport is Bhow far Pudong Airport was Chow can we get to Pudong Airport Dwhen was Pudong Airport built 10Mike wants to know if_ a picnic tomorrow.Yes. But if it _, well visit the museum instead. Ayou have; will rain Byou will have

16、; will rain Cyou will have; rains Dwill you have; rains 11 Why didnt Nick come to school yesterday？_ he was ill. AAfter BWhere CWhen DBecause 12This box is _ heavy _ I cant carry it. Atoo; to Bso; that Cvery; that Dtoo; that 13I dont know _ he still lives here. Awhere Bwhat Cwhen Dwhether 14. -Do yo

17、u know if he _ to play basket ball with us? -I think he will come if he _ free tomorrow. A. comes; is B. comes; will be C. will come; is D. will come; will be15. In the zoo if a child _ into the water and cant swim, the dolphins may come up _ him. A. will fall; to help B. falls; to help C. will fall

18、; help D. falls; helping16.In the bookshop，a reader asked the shop keeper _Who Moved MyCheese was an interesting book.A.thatB.howC.whatD.if17、I want to know _ you have a brother.A.ifB.thatC.thoseD.them18、We will go hiking if it tomorrow.A.will be fine B.is fine C.be fine D. is gong to be fine19、Maybe you if you make so