If引導的條件狀語從句引導的條件狀語從句潘店鎮(zhèn)中學 1應用2例句例句：If people obey the traffic rules,there will be fewer accidents.if引導的條件狀語從句引導的條件狀語從句if:從屬連詞，意思是：從屬連詞，意思是：“如果，假如，倘若如果，假如，倘若”從句從句主句主句There There willwill be fewer accidents be fewer accidents if if people obey the traffic rules.people obey the traffic rules.原句可改為：原句可改為：if引導的條件狀語從句既可以放在句子前，引導的條件狀語從句既可以放在句子前，也可以放在句子后。也可以放在句子后。從句位于主句之前時，常用逗號將其與主句隔開從句位于主句之前時，常用逗號將其與主句隔開。結構結構：2應用2主句謂語中也可以含有情態(tài)動詞，主句謂語中也可以含有情態(tài)動詞，如：如：must,can,could,should等等時態(tài)時態(tài)：if引導的條件狀語從句，引導的條件狀語從句，主句用一般將來時（主句用一般將來時（will）,從句用一般現(xiàn)在時。從句用一般現(xiàn)在時。例句例句：If people obey the traffic rules,there will be fewer accidents.主句謂語中也可以用主句謂語中也可以用had better(not)do,提建議提建議例句例句：如果交通指示燈是紅的，你必須停下來等一等。如果交通指示燈是紅的，你必須停下來等一等。eg:If the traffic lights are red,you must stop and wait.例句：如果你想減肥，你最好鍛煉。例句：如果你想減肥，你最好鍛煉。eg:If you want to lose weight,you had better take some exercise.3應用2if的反義詞：的反義詞：if.not.=unless,意思是：意思是：“如果不，除非如果不，除非”I wont go there unless I hear from you.(同義同義句句)I wont go there _ I _hear from you.if dont I wont go to the party if I am not invited.(同義同義句句)I wont go to the party_ I am invited.unless4應用2變換：變換：1.有有if引導的條件狀語從句的復合句中，當主句和從句的引導的條件狀語從句的復合句中，當主句和從句的主語均為主語均為you時，可轉換為時，可轉換為“祈使句，祈使句，and+簡單句簡單句”或或“祈使句，祈使句，or+簡單句簡單句”You can pass the exam if you work hard.-，and you will pass the exam.If you dont hurry up,you will be late again.Hurry up,-you will be late again.Work hardor5應用22.借助介詞借助介詞with 或或without來轉換。來轉換。例如例如:If you help me,Ill finish my job soon.-,Ill finish my job soon.如果你幫我，我將很快完成我的工作。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 -.如果沒有水，魚可能會死。如果沒有水，魚可能會死。With your helpwithout water6應用2 注意事項注意事項 1.在在if引導的條件狀語從句中，當主句是一般將引導的條件狀語從句中，當主句是一般將來時時，不能夠使用來時時，不能夠使用be going to結構，而要用結構，而要用will。例如：例如：Ill help you with your English if I am free tomorrow.如果明天我有空，我會幫你學英如果明天我有空，我會幫你學英語。語。2.在在if引導的條件狀語從句中不能夠使用引導的條件狀語從句中不能夠使用some，而要用而要用any。例如：例如：If you have any questions to ask,please come to my office.如果你有問題要問的如果你有問題要問的話，請到我辦公室來。話，請到我辦公室來。7應用2If 在賓語從句中翻譯為在賓語從句中翻譯為“是否是否”If 在條件狀語從句中翻譯為在條件狀語從句中翻譯為“如果如果”Ill go to see you if I am free next week.I want to know if he is a teacher.whether1.if 在句中的含義不同在句中的含義不同8應用22.if 在從句中的位置不同在從句中的位置不同If 引導的賓語從句放在主句之后；而引導的賓語從句放在主句之后；而if引引導的狀語從句可放在主句之前也可放在主導的狀語從句可放在主句之前也可放在主句之后句之后=If it doesnt rain,I will go out tomorrow.I will go out tomorrow if it doesnt rain.I dont know if the train has arrived.If 引導的條件狀語從句放于句首時多用逗號隔開；引導的條件狀語從句放于句首時多用逗號隔開；而而if引導的賓語從句則不能。引導的賓語從句則不能。9應用21.Can you tell me if she can come to the meeting?2.She will not go there if it is rainy tomorrow.3.I cant guess if she will be angry.4.If we help each other,we both will get good results.10應用23.時態(tài)要求上有區(qū)別時態(tài)要求上有區(qū)別If 引導條件狀語從句的時態(tài)為一般現(xiàn)在時引導條件狀語從句的時態(tài)為一般現(xiàn)在時 記住記住“主將從現(xiàn)主將從現(xiàn)”1.I want to know if there a sports meeting next month.doesnt rainwill be2.If it ,well hold it.If 引導的賓語從句的時態(tài)由主句及本身時引導的賓語從句的時態(tài)由主句及本身時態(tài)決定；態(tài)決定；11應用21 If I _(not understand）,I will ask my teacher for help.2 If I _(copy)your homework,I will cheat myself.3 If she _(not get)up early,shell miss the early bus.4 If your mother_(buy)the book for you,it will be good for your study.dont understand copy doesnt get buys12應用25.If you _(not work)hard,you _(not pass)the exam.6.If she _(mend)the computer,her father _(not blame).7.If your brother _(break)the window,he will feel very sorry for that.8.If the computer (not work),mend it please.dont workwont passmendswont blame breaksdoesnt work13應用29.If she _(not be)interested in math,she will find it very boring.10.If you _(get)high scores,your parents will be proud of you.11.If you _(be)happy,we will be happy.12.If she (translate)the sentence word by word,she _(get)its true meaning.isnt getaretranslates will get14應用21.If you _ to the party,youll have a great time.A.will go B.went C.go D.going2 I _ her the answer if she _me.A.can tell,will ask B.will tell,will ask C.would tell,ask D.will tell,asksCD3.What are you going to do tomorrow?-Well go to the library tomorrow if it _.A.isnt rain B.rain C.wont rain D.doesnt rain4.What will you do if you _ to the old folks home visit?A.go B.went C.going D.will goAD15應用216應用2