初中語法之if條件狀語從句

1、If從句（條件狀語從句）從句（條件狀語從句）主句主句+if條件狀語從句條件狀語從句 if條件狀語從句，條件狀語從句，+主句（從句后加逗號）主句（從句后加逗號）if條件狀語從句要用一般現(xiàn)時。條件狀語從句要用一般現(xiàn)時。句型結構句型結構時態(tài)時態(tài) If 條件狀語從句條件狀語從句If Im hungry,I will_. If Im tired, I will_. eat some foodhave a restIf Im ill,_. I will see a doctorIf Im late,_.I will say sorry If it rains tomorrow,I_.will watch

2、TV at homeIf it _ tomorrow,_.Ill play basketballdoesnt rainI wont_.play basketballIf you are free this weekend,what will you do ?If I am free ,sleepwatch TVplay computer gamespracticeif條件狀語從句條件狀語從句(2)句子特點：句子特點：1.if從句中用一般現(xiàn)在時，表示未來的一種條件，從句中用一般現(xiàn)在時，表示未來的一種條件，從句中可以加時間狀語。從句中可以加時間狀語。2.當當if表示未來的條件時，主句中用一般將來時

3、。表示未來的條件時，主句中用一般將來時。句型結構：句型結構：主句主句+if條件狀語從句條件狀語從句 if條件狀語從句，條件狀語從句，+主句（從句后加逗號）主句（從句后加逗號）3.時態(tài)時態(tài)：if一般現(xiàn)在時，一般現(xiàn)在時，+主句一般將來時或主句一般將來時或（can/ may /must +v.)e.g. 1.If you dont get up early, you will be late for school .你如你如果不早點起床，上學就會遲到。果不早點起床，上學就會遲到。2. If I play games on it , it will go wrong .如果我用它玩游戲，它就會壞掉。如

4、果我用它玩游戲，它就會壞掉。3. If you finish the homework， you can go home如果你作業(yè)做完了就可以回家了。如果你作業(yè)做完了就可以回家了。 4. If you want to lose weight you must/should eat less bread. 如果你想減肥，你必須少吃面包。如果你想減肥，你必須少吃面包。5.If you heat ice it turns to water. (也可用也可用will turn)如果把冰加熱，它就會化成水。如果把冰加熱，它就會化成水。vif條件句不一般條件句不一般,幾個要點記心間。幾個要點記心間。v條件

5、句放在前條件句放在前,逗號要放句中間。逗號要放句中間。v條件句表可能條件句表可能,主句多用將來時；主句多用將來時；v條件句表事實條件句表事實,主句常用現(xiàn)在時。主句常用現(xiàn)在時。vif條件句有特點條件句有特點,現(xiàn)在時把將來替；現(xiàn)在時把將來替；v這個規(guī)則要牢記這個規(guī)則要牢記!if條件句歌訣條件句歌訣1.If he_ (not, do it ), I_(do) it.2.If you _ (be) late for school ,my teacher _(be) angry.arewill be3 If she_ (win) the prize ,we _(be) happy.winswill be

6、4.If I _ (not,eat )so much ,I _(get) thinner.5.If you _(tell) them, they _ (not,believe) you.dont eatwill gettellwont believe6 I _(stay) at home,If it _( rain).7.If it _(not,rain) ,I _( go) out.8. we _(play) football, If it is _(sun) .9.If she _(become) a star ,her parents _ (not,send) her away 10.H

7、e _(watch) TV ,if he _(be) free.will stayrainsdoesnt rainwill gowill playsunnybecomeswont sendwill watchisdoesnt dowill do-Im always tired in the morning.-If you go to bed early, you wont be tired in the morning.Giving suggestions:-I get thirsty when I run.-If you take some water with you,you wont g

8、et thirsty when you run.I worry so much about my schoolwork.-If you always work hard,you wont worry about your schoolwork.You should work hard!Unit 3 activity 1 Rewrite the sentences with if:Listen in class, or you wont understand what to do.If you dont listen in class, you wont understand what to d

9、o.1) Eat some breakfast, or youll get hungry at school.2) Hurry up! Well be late!3) Read the instructions carefully. Then youll know what to do.If you dont eat some breakfast, youll get hungry at school.If you dont hurry up, well be late.If you read the instructions carefully, youll know what to do.

10、Activity2.Complete the sentences I want to get high scores. If _(work hard/ do well)you work hard, you will do well.1.-how can I remember my friends birthdays? -If_ (keep a note in your diary / not forget).2.-Its late, but I dont want to go to sleep. -If _ (not get enough sleep/ feel tired at school

11、).you keep a note in your diary, you wont forget.you dont get enough sleep, youll feel tired at school.3.-I dont like speaking English outside the classroom.-If_(not practice / not improve).4.-Should I tell my teacher I dont understand the homework?-If_(not tell her / she not able to help you).5.-Is

12、 it OK if I watch TV for six hours?-If_(you watch too much / eyes hurt).you dont practice, you wont improve.you dont tell her, she wont be able to help you.you watch too much TV, your eyes will hurt.if的用法的用法2.引導條件狀語從句：引導條件狀語從句：譯為譯為“如果，假如如果，假如”(1) if從句從句+祈使句祈使句(2) if從句從句+主句（一般將來時）主句（一般將來時）1.引導賓語從句引導賓

13、語從句：譯為：譯為“是否是否”，表示不確定的概，表示不確定的概念。念。I dont know if your father can come together . Can you tell me if miss your parents ?e.g. If I were you , I would invite him to the party .如果如果我是你，我會邀請他參加聚會。我是你，我會邀請他參加聚會。If he had hurried ,he could have caught the train .如果他抓緊點，他會趕上火車的。如果他抓緊點，他會趕上火車的。 If I were to

14、 go abroad ,I would go to America.如果我出國了，我會去美國。如果我出國了，我會去美國。3.非真實條件句（虛擬語氣）非真實條件句（虛擬語氣）：表示不可實現(xiàn)的條件：表示不可實現(xiàn)的條件或根本不存在的條件?；蚋静淮嬖诘臈l件。從句多用一般過去時或過去完成時，表示對現(xiàn)在或從句多用一般過去時或過去完成時，表示對現(xiàn)在或過去的一種假設。過去的一種假設。( ) 6. Mike wants to know if _ a picnic tomorrow. Yes. But if it _, well visit the museum instead. A. you have/ wi

15、ll rain B. you will have/ will rain C. you will have/ rains D. will you have/ rains ( ) 7. I really dont know if she _ it when she _. A. finds/ arrives B. finds/ will arrive C. will find/ will arrive D. will find/ arrives（ ）4. I dont know if_ tomorrow. A. it doesnt rain B. the rain will stops C. the

16、 rains wont stop D. it wont rain（ ）5. The volleyball match will be put off (推遲） if it _. A. will rain B. rains C. rained D. is raining（ ）1. Be careful, if you_ want to make mistakes. A. wont B. dont C. didnt D. not（ ）2. Work hard if you _ to get a good mark. A. wanted B. wanting C. want D. will want（ ）3. -I want to know if you_ to the par