if條件狀語從句_語法

1、 If從句從句 條件狀語從句條件狀語從句What will I do if it is sunny this weekend?Part1:If 的用法 1.I want to know if he will go to park with us.2. We will have a picnic if it doesnt rain.3. If you boil water, it becomes steam. 4. If you feel tired must .賓語從句賓語從句條件狀語從句條件狀語從句語法語法1：if作為賓語從句作為賓語從句的引導詞，引導賓語從的引導詞，引導賓語從句。（是否）句

2、。（是否）語法語法2：if（如果）引（如果）引導的條件狀語從句導的條件狀語從句賓語從句賓語從句 if 用于賓語從句中用于賓語從句中原句式原句式引導詞引導詞從句語序從句語序一般一般疑問句疑問句whether/if改為陳述句改為陳述句 語序語序由從屬連詞由從屬連詞whether, if 引導的賓語從句引導的賓語從句e.g. 1. I want to know _. （他是否跟我們一起去公園）（他是否跟我們一起去公園）2. Ask him _. （他是否能來）（他是否能來）3. I didnt know _.（是否要下雨）（是否要下雨） if (whether) he will go to the

3、park with us whether (if) he can come whether it was going to rain or not當句末為當句末為or not時，引導詞只能用時，引導詞只能用whether而不能用而不能用if.If 與whether 的區(qū)別I dont know _ he will come or not.I dont care of _ he is handsome.He wondered _ to stay here the next week._ he will come is not decided. 與與or not 連用只能用連用只能用whether

4、介詞后只能用介詞后只能用whether與與to do 不定式連用只能用不定式連用只能用whether作主語只能用作主語只能用whetherIf 引導條件狀語從句引導條件狀語從句 Complete the sentences with the correct form of the words.1.If you _(listen) to the music, _ (buy) a CD. 2. If he_ (be) late for school, _ (not wait ) for him.3. If you _ (buy) a new camera, _ (get) a good one.

5、4. If the light _ (not come) on, _ (wait) for one minute.isbuygetdoesnt comewaitdont wait listenbuy祈使句祈使句+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，+祈使句（從句后加逗號）祈使句（從句后加逗號）if條件狀語從句要用一般現(xiàn)在時。條件狀語從句要用一般現(xiàn)在時。句型結(jié)構(gòu)句型結(jié)構(gòu)時態(tài)時態(tài)If 條件狀語從句（條件狀語從句（1）What will you do if youre happy?vIf Im happy, I will _. vIf Im happy, I will _.

6、vIf Im happy, I will _.vIf Im happy, I will _.clap my handsstamp my feetwink my eyesnod my headIf 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 TV at homeIf it _ tomorrow,_.Ill play ba

7、sketballdoesnt rainI wont_.play basketballIf it is sunny this weekend, what will you do ?If it is sunny this weekend, I _ football with my classmates.If it is sunny this weekend, I_. will playIf it is sunny this weekend, what wont you do ?If it is sunny this weekend, I _.If it is sunny this weekend,

8、 I _.Wont stay at home wont watch television If 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。表示未來的條件時，主句中用一般將來時。句型結(jié)構(gòu)：句型結(jié)構(gòu)：主句主句+if

9、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.)If條件句：條件句用于陳述語氣，表示假設的情況可能發(fā)生，其中 if 是“如果”的意思。構(gòu)成條件從句主句時態(tài)If一般現(xiàn)在時主語shall/will+動詞原形例句If he comes,he will take us to the zoo.用法：1. 如果主句是一般將來時，從句則用一般現(xiàn)在時。如果主句是一般將來時，從句則用一般現(xiàn)在時。 If it rains（從句）， I will s

10、tay at home. Ill go with you if you dont want to go alone（從句）. 2.如果主句含有如果主句含有must, may, can 等情態(tài)動詞，從句也要用等情態(tài)動詞，從句也要用一般現(xiàn)在時。一般現(xiàn)在時。 If you drive too fast, you may have an accident. You must stop if the traffic is red.3. 如果主句是祈使句，從句同樣要用一般現(xiàn)在時。如果主句是祈使句，從句同樣要用一般現(xiàn)在時。 Dont go and play football if you dont fini

11、sh your homework. Please call me if he comes next Sunday.4.表示假設，表示將會發(fā)生和可能發(fā)生的事，表示假設，表示將會發(fā)生和可能發(fā)生的事，或進行提醒警告?；蜻M行提醒警告。If +句子（一般現(xiàn)在時），句子（一般現(xiàn)在時），+主句（主語主句（主語will/may/can) +動詞）動詞） If you finish your homework , you can go out and play. If I have enough money next year , I will go to travel . 下列從句中的下列從句中的will不是

12、將來時助動詞，而是情態(tài)動詞。不是將來時助動詞，而是情態(tài)動詞。 翻譯為翻譯為“愿意愿意”。 If you will excuse me,I really must go to bed .如果你能原諒我的話，我真的要睡覺了。If you will wait a minute ,Ill go and tell my mother that you are here . 如果你愿意等一會的話，我去告訴我媽媽你來了。試比較下列句子：試比較下列句子： If you see him tomorrow ,give him this book . 如果你明天去看他，給他這本書。 If you will see

13、him tomorrow ,give him this book . 如果你明天愿意去看他，給他這本書。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e.g. 1.If you dont get up early, you will be late for school .你如你如

14、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 t

15、o 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。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 be4.If I _ (not,eat )so much ,I _(get) thinner.5.If you _(tell) them, they _ (not,believe) you.

16、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.He _(watch) TV ,if he _(be) free.will stayrainsdoesnt rainwill gowill playsunnybecomeswont sen

17、dwill watchisdoesnt dowill do( ) 5. Mike wants to know if _ a picnic tomorrow. Yes. But if it _, well visit the museum instead. A. you have/ will rain B. you will have/ will rain C. you will have/ rains D. will you have/ rains ( ) 6. I really dont know if she _ it when she _. A. finds/ arrives B. fi

18、nds/ will arrive C. will find/ will arrive D. will find/ arrives （ ）4. 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. wante

19、d B. wanting C. want D. will want（ ）3. -I want to know if you_ to the party tomorrow. - I will if I_ free. A. will come; am B. come; am C. will come; will be D. come; will beexercisesBCABCD-Im always tired in the morning.-If you go to bed early, you wont be tired in the morning.Giving suggestions:-I

20、 get thirsty when I run.-If you take some water with you,you wont get 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 wh

21、at to do.If you dont listen in class, you wont understand what to do.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

22、late.If you read the instructions carefully, youll know what to do.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 wan

23、t to go to sleep. -If _ (not get enough sleep/ feel tired at school).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 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