If引導的從句

1、年 級初二學 科英語版 本外研社（新標準）課程標題If引導的從句編稿老師李晶一校林卉二校黃楠審核劉曉軍一、學習目標1. 掌握if引導的賓語從句的用法。2. 掌握if引導的條件狀語從句的用法。3. 能恰當使用含有if引導的條件狀語從句的復合句中主從句的時態(tài)。二、重點、難點1. 含有if引導的條件狀語從句的復合句中主從句的時態(tài)。2. If引導的賓語從句與條件狀語從句的區(qū)別。 三、考情分析通常在單項選擇、完形填空或補全、完成句子等題型中考查，分值約34分。四、知能提升（一）知識講解【認知講解】I. if引導的賓語從句if 引導賓語從句時，意思為：是否，從句的時態(tài)通常要和主句保持一致?！纠洹縄 wa

2、nt to know if he lives there.我想知道他是否住在那兒。He asked me if I could help him.他問我是否能幫他?！究疾辄c】if、whether引導的賓語從句的區(qū)別1. if或whether引導賓語從句時，作“是否”講，常放在動詞ask、see、say、know和find out等后面。一般情況下，兩者常可換用，在口語中多用if?！纠洹?Nobody knows whether / if it will rain tomorrow. 沒有人知道明天是否下雨。 Lucy asked whether / if they had a cotton

3、sweater. 露西問他們是否有棉制的毛衣。2. if或whether引導賓語從句時，要注意三個方面，即連詞、語序和時態(tài)。if或whether既不能和that 或其他連詞（副詞）同時使用，也不能省略。【例句】我不知道他今天是否會來。誤 I dont know that if(whether) he will come here today.正 I dont know if(whether) he will come here today.他走過來看看貓是否出了毛病。誤 He came to see what if (whether) there was anything wrong with

4、 his cat .正 He came to see if (whether) there was anything wrong with his cat .if或whether引導賓語從句時，雖具有疑問的意義，但其從句應用陳述句的語序?！纠洹?Did you know the way to the hospital? The old woman asked me.The old woman asked me if / whether I knew the way to the hospital.老婦人問我是否知道去醫(yī)院的路。 if或whether引導的賓語從句應和主句的時態(tài)保持一致。即主句

5、為一般現(xiàn)在時，從句用任一種時態(tài)；主句為一般過去時，從句則用過去時中的任一種時態(tài)?！纠洹?I dont know if (whether) he has come here. 我不知道他是否來過這兒。Tom asked if (whether) I had read the book. 湯姆問我是否看過這本書。3. 只能用whether的情況在動詞不定式之前只能用whether：【例句】I cant decide whether to stay.我不能決定是否留下。在whether or not 的固定搭配中：【例句】 I want to know whether its good news

6、or not. 我想知道它是不是好消息。在介詞后，只能用whether：【例句】 His father is worried about whether he loses his work. 他的父親擔心他是否會失去工作。用if會引起歧義時：【例句】Could you tell me if you know the answer? 這句話有兩種意思：“你能告訴我你是否知道答案嗎？”或“如果你知道答案，請告訴我，好嗎？”。如用whether則可避免歧義。 【考題鏈接】I dont know _ they could pass the exam or not.A. why B. if C. tha

7、t D. whether答案：D解題思路：本題考查if與whether的區(qū)別，在whetheror not的固定搭配中通常只用whether。II. if引導的條件狀語從句1. 含義條件狀語從句是在復合句中作條件狀語的句子。表示假如有從句的動作發(fā)生就會有主句的動作發(fā)生，條件狀語從句常由從屬連詞if引導?！纠洹縔ou will catch the bus if you get up early.如果你早起的話，就能趕上公共汽車。2. 類別主祈從現(xiàn)：主句是祈使句, 從句是由if引導的使用一般現(xiàn)在時的句子?！纠洹?If you want to go, please tell me. 如果你想去，

8、請告訴我。Print the photo if you like it. 如果你喜歡這照片就把它打印出來。主將從現(xiàn)：指if引導的條件狀語從句用一般現(xiàn)在時，主句用一般將來時?！纠洹?If it doesnt rain tomorrow, well go to the Great Wall.如果明天不下雨，我們就會去長城。 If you dont get up early, you will be late for school. 如果你不早點起床，你上學就會遲到。3. if引導的條件狀語從句用法：（1）位置if引導的條件狀語從句，既可放在主句之前也可放在主句之后。當從句置于主句之前時，常用逗號

9、與主句隔開?！纠洹縔ou will catch the bus if you get up early.=If you get up early, you will catch the bus.如果你早起的話，就能趕上公共汽車。（2）時態(tài)應遵循主、從句時態(tài)呼應的原則。當主句是一般現(xiàn)在時（包含祈使句和含情態(tài)動詞can, may, must等的句子），從句也用一般現(xiàn)在時?！纠洹縔ou must see the doctor if you are ill.如果你生病了，你必須去看醫(yī)生。If you want to go skating, wear warm clothes.如果你想去溜冰，穿上暖

10、和的衣服。如果主句是一般將來時，從句必須用一般現(xiàn)在時?！纠洹?You will be late for school if you get up late.如果你起晚了，你上學將遲到。If it rains tomorrow, we wont go to the Great Wall.如果明天下雨，我們就不去長城了。（3）在if引導的條件狀語從句中，當主句是一般將來時時，不能使用be going to結構，而要用will。【例句】Ill help you with your English if I am free tomorrow.如果明天我有空，我會幫助你學英語。（4）在if引導的條件狀

11、語從句中不能使用some，而要用any?！纠洹縄f you have any questions to ask, please come to my office.如果你有問題要問的話，請到我辦公室來。（5）同義句轉(zhuǎn)換if引導的條件狀語從句可轉(zhuǎn)換成簡單句，其方法如下：* 借助“祈使句+and/ or+簡單句”結構。其中and表示句意順承，or表示句意轉(zhuǎn)折?！纠洹縄f you work hard, youll pass the exam.=Work hard, and youll pass the exam.如果你努力學習，你就會通過考試。If you dont hurry up, youl

12、l be late.= Hurry up, or youll be late.如果你不快點，你將會遲到。*借助介詞with 或without來轉(zhuǎn)換?！纠洹縄f you help me, Ill finish my job soon.=With your help, Ill finish my job soon.如果你幫我，我將很快完成我的工作。If there is no water, fish may die.= Fish may die without water.如果沒有水，魚可能會死。另外，if從句還表示不可實現(xiàn)的條件或根本不可能存在的條件，即一種虛擬的條件或假設。從句多用一般過去時

13、或過去完成時，表示對現(xiàn)在或過去的一種假設。【例句】If I were you，I would invite him to the party如果我是你，我會邀請他參加聚會。 I would have arrived much earlier if I had not been caught in the traffic要不是交通堵塞，我會來得更早一些。4. 口訣：if 條件句不一般，幾個要點記心間； 條件句，放在前，逗號要放句中間。 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。 III. If引導的賓語從句和條件狀語從句的區(qū)別if引導條件狀語從句時意為“如果”，引導賓語從句時

14、意為“是否”，可用whether替換?！纠洹?) We will go out if it is fine tomorrow. 如果明天天好，我們就出去。2) I dont know if the train has arrived. 我不知道火車是否已經(jīng)到達。句1)中if引導的是狀語從句。這個從句表示“條件”。句2)中if引導的是賓語從句，充當謂語動詞dont know的賓語?！究碱}鏈接】 I dont know _ he will come tomorrow. _ he comes, Ill tell you A. if; Whether B. whether; Whether C. i

15、f; That D. if; If答案：D解題思路：第一個空處為賓語從句的引導詞，用if、whether都可以；第二個空為條件狀語從句的引導詞，需用if，綜合考慮，D項正確。（二）提分技巧1. 熟練掌握if引導的賓語從句與條件狀語從句的特點。 2. 熟知if引導的賓語從句與條件狀語從句引導詞的區(qū)別。 （三）即學即練I. 句型轉(zhuǎn)換 1. Do they want fried chicken? He asked the boys.(改為賓語從句) He asked the boys _they _fried chicken. 2. Was the watch made in Shanghai? I

16、 dont know.(改為賓語從句) I dont know _the watch _made in Shanghai.3. “Do you want to try something new?” Toms mother asked him.(同義句轉(zhuǎn)換)Toms mother asked him _to try something new.答案：1. if / whether, wanted 2. if / whether, was 3. if / whether he wanted II. 用括號中所給動詞的適當形式填空1. If it _ (not rain)tomorrow, _(l

17、et) us go shopping.2. Please _ (tell)me if you _ (go).3. If you _ (be)ill, you _ (have)to see the doctor.4. I _ (leave)for Beijing if it _(not snow) this afternoon.答案：1. doesnt rain, let 2. tell, go 3. are, have 4. will leave, doesnt snowIII. 將下列句子翻譯成英語。1. 如果明天不下雨，我就和同學們?nèi)ヒ安?。_.2. 如果周日你去購物的話，我就去。_.3.

18、如果你想減肥（lose weight），就鍛煉身體吧。_.4. 如果冬天來了，春天還會遠嗎？_.5. 如果可能的話，我就去火車站接你。_.答案：1. If it doesnt rain tomorrow, I will have a picnic with my classmates.2. I will go shopping on Sunday if you do.3. Take some exercise if you want to lose weight.4. If winter comes, can spring be far behind?5. If (it is) possibl

19、e, Ill meet you at the train station.下學期期中復習（一）一、預習新知Module 1-Module 5重點基礎知識二、預習點撥思考問題一：能否先把這5個模塊的重點單詞、短語、語法整理一下？思考問題二：我們已經(jīng)學習了哪些語法？哪些還是你比較薄弱的？（答題時間：45分鐘）一、用所給動詞的適當形式填空。 1. If you _(feel) tired, you _ (have) to have a rest.2. Where _ he _(see) the film if he _(have) time?3. If there _(be) fewer trees

20、, there _(be) more pollution.4. He _(dress) more casually if he _(not work) on weekends.5. If Marcia _(live) alone, she _(keep) a pet parrot.6. Lana _(buy) a new dress if the old one _(be) out of style.7. The twins _(fight) if they_(argue).8. I _(have) a bake sale if I _(need) money for education.9.

21、 Peter _(send) me a beautiful souvenir if he _(tour) Spain.10. If Mr Green _(say) I am hard- working, my parents _(feel) glad.11.I _(go) to the beach if it_ (not rain) this week.12. _they _(have) a match if the P.E. teacher _(be) busy?13. He _(write) a letter to his grandparents if he _(get) his rep

22、ort card this week.14. If she _(get) up late, she _ (not catch) the early bus.15. Peter _(major) in English if he _(pass) the exams in Peking University.二、完成句子（每空一詞）。1. 如果你要過馬路，不要亂跑。_ _ around if you cross the road.2. 明天如果下雨的話，我們將呆在家里。We _ _ at home if it _ tomorrow.3. 如果你能說好英語的話，你就可以容易地與外國人交談。If yo

23、u can _ English well, you _ _ _ foreigners easily.4. 如果你對別人好，人們也會對你好。If youre nice to people, they _ _ _ to you, too.5. 如果學生不對考試如此擔心的話，他們會更開心的。If students dont worry about exams so much, they _ _ _.6. 他如果電視看太多了，他的父母會不高興。If he _ TV too much, his parents _ _ unhappy.7. 如果我們?yōu)樗M織生日聚會，大家都會來的。Everyone _ _

24、 if we _ a birthday party _ him.8. 如果明天不下雨，我會和你一起去公園的。If it _ _ tomorrow, I _ go to the park _ you.9. 如果他有空，他會幫助你的。If he _ _, he _ _ you.10. 如果Tom考試不及格，他就沒有機會上高中了。Tom _have the _to go to the senior high school if he _ _ the exams.三、同義句轉(zhuǎn)換。1. Study hard, or you wont pass the exam.If you study hard, yo

25、u _ _ the exam.2. Take a taxi, and youll catch the train._ you _ a taxi, youll catch the train.3. If you go to bed early, you wont feel tired in the morning._ _ _ early, _ you wont feel tired in the morning.4. If you dont work hard, your teacher will probably be angry._ _, _ your teacher will probab

26、ly be angry.5. Breathe deeply for one minute, and youll feel relaxed._ you _ deeply for one minute, you _ _ relaxed.四、閱讀下面的廣告，然后用“if., .will.”的句式回答問題。Travel BrochureCheap Cheap Cheap. Beijing for the weekend. 3D/2N. Book Now.Five Star HotelSave 50%Four Star HotelSave 40%Three Star HotelSave 30%Book

27、before December 31st. Breakfast Included.City Tour 50RMB. Visit the Great Wall 100 RMB.1. How much will you save if you stay at the Four Star Hotel?_2. How much will you save if you stay at the Three Star Hotel?_3. What will happen if you book after December 31st?_4. How much will you have to pay if

28、 you want to go on the City Tour?_5. How much will you have to pay if you want to visit the Great Wall?_五、單項選擇1. If you _ to the party, youll have a great time. A. will go B. went C. go D. going2. It will be a long time _ Peter _ his work.A. since, has finished B. after, finishes C. when, will finis

29、h D. before, finishes3. What will father _ us from Japan? A. take B. bring C. carry D. make4. Weifang is famous _ kites. A. for B. to C. on D. with5. I _ her the answer if she _me.A. can tell, will ask B. will tell, will askC. would tell, ask D. will tell, asks6. What are you going to do tomorrow? W

30、ell go to the library tomorrow if it _.A. isnt rain B. rain C. wont rain D. doesnt rain7. Do you know when he will come back tomorrow?Sorry, I dont know. When he _ back, Ill tell you.A. comes B. will come C. come D. may come8. What will you do if you _ to the old folks home visit?A. go B. went C. go

31、ing D. will go9. If I eat _ food, Ill be very fat.A. too many B. many too C. too much D. much too10. Ill give the book to him if he _ here next Sunday.A. will come B. comes C. is coming D. came11. There _an English film in our school tomorrow.A. is going to have B. will have C. is going to be D. has

32、12. Could you tell us where _？ A. will the next Olympic Games held B. the next Olympic Games will be held C. would the next Olympic Games be held D. the next Olympic Games would be held13. When my mother returned last night, I _a book. A. read B. am reading C. was reading D. am going to read14. What _ you _ when it began to rain? A. do, do B. wer