1、IF 引导的条件状语从句引导的条件状语从句 if?Do you know the meaning of.What will happen if you heat ice?It will melt.I heat ice.What will happen if you drop a glass?It will break.I drop a glass.What will happen if you stand in the rain?I will get wet.I stand in a rain.What will happen if you come to school late?I will
2、 miss some classes.I come to school late.What can you FINDit will melt.I heat ice,it will break.I drop a glass,i will get wet.I stand in a rain,I will miss classes.I come to school late,clausemain clause主句主句一般将来时一般将来时It will be sunny tomorrow.We will have a trip tomorrow.We will have a trip it is su
3、nny tomorrow.IfIf引导一个条件状语从句引导一个条件状语从句来谈论来谈论“可能的可能的行动导致的可能的结果行动导致的可能的结果”。如果主句。如果主句用用_时，则从句用时，则从句用_时，时，简称简称“主主将将从从现现”一般将来一般将来一般现在一般现在例句：例句：If people obey the traffic rules,there will be fewer accidents.引导的条件状语从句引导的条件状语从句:从属连词，意思是：从属连词，意思是：从句从句主句主句if引导的条件状语从句既可以放在句子前，也可以放在句子后。引导的条件状语从句既可以放在句子前，也可以放在句子后
4、。we do not protect giant pandas,they will die.If I come to school late,I will miss some classes.I will miss some classes I come to school late.What will happen if you come to school late?It is going to rain tomorrow.I will stay in bed.it rains I will stay in bed.I will stay in bed it rains 主句谓语主句谓语中
5、也可以含有情态动词，中也可以含有情态动词，如：如：等等主句谓语中也可以用主句谓语中也可以用had better(not)do,提建议提建议例句例句：如果交通指示灯是红的，你如果交通指示灯是红的，你必须必须停下来等一等。停下来等一等。If the traffic lights red,you must stop and wait.例句：如果你想减肥，你例句：如果你想减肥，你最好最好锻炼。锻炼。If you want to lose weight,you had better take some exercise.n1.在在if引导的条件状语从句中，当主句是一般将引导的条件状语从句中，当主句是一般
6、将来时时，不能够使用来时时，不能够使用be going to结构，而要用结构，而要用will。n nIll help you with your English if I am free tomorrow.n 如果明天我有空，我会帮你学英语。如果明天我有空，我会帮你学英语。n n2.在在if引导的条件状语从句中不能够使用引导的条件状语从句中不能够使用some，而要用而要用any。n If you have any questions to ask,please come to my office.如果你有问题要问的话，请如果你有问题要问的话，请到我办公室来。到我办公室来。2Give some
7、advice！1.I sometimes bring the wrong books to school.If you check your timetable every night，you will know which books to bring.2.I was away from school today,I do not know what homework to do.If you call your friends,they will tell you what homework to do.3.I hate getting up,I always feel tired in
8、the morning.If you go to bed early,you will not feel tired in the morning.4.I do not know what this word means.If you look it up in the dictionary,you will find out its meaning.1._(make)the wheels round(圆圆)，they_easily.(turn)if you makewill turnHow to make the wheels run2.The seeds _in the soil.(gro
9、w/plant)will grow if you plant themHow to make the seeds grow3._ another wing,it _.(put on/fly)if you put onwill flyHow to make the plane fly4._ your coat,you _ so cold.(put on/not feel)If you put onwill not feelHow to make him not feel coldwill not go bad if you put it How to make the meat not go b
10、ad6.You_your classes.(see clearly/wear)will see clearly if you wearHow to see clearlyExerciseBefore Exercise After Exercise 31 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_
11、(buy)the book for you,it will be good for your study.dont understand copy doesnt get buys5.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 pl
12、ease.dont workwont passmendswont blame breaksdoesnt work9.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
13、 getaretranslates will get1.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
14、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 goADWhy do I want to go to Beijing Zoo?1.If I _(go)to Beijing Zoo,I _(learn)a lot about animals.2.If I _(arrive)at noon,I _(see)the feeding of animals.3.If I _(find)the Monkey Hill,I _(
15、have)fun there.gowill learnarrivewill seefind will have4.If I _(watch)the animals carefully,I _(get)enough information for my class report(报报告告).5.If I _(finish)my report(报告报告),I _(be)very happy.watchwill getfinishwill beWhy do I want to go to Beijing Zoo?Fill in the blanks1.If Eddie _(die),no one _
16、(look)after Hobo.2.If Eddie and Hobo _(not have)enough food,they _(share)it.3.Wild animals _(be)in danger if hunters _(keep)killing them.dieswill lookdont havewill sharewill bekeep4.We _(keep)pandas safe from danger if we _(build)more reserves.5.You _(see)some squirrels if you _(go)to the zoo.6.The
17、baby panda _(live)on his own if his mother _(leave)him for two whole days.will keepbuild will seegowill liveleavesFill in the blanks7.If we _(build)the giant panda reserves,we _(encourage)them to leave.8.If we _(not do)anything,soon there _(be)no pandas in the world.buildwill encouragedont dowill be
18、Fill in the blanks拓展：拓展：当主句的动作表示真理或必然的结果时（结果一定会发生），主句和if引导的条件状语从句时态都用一般现在时。1.If you heat ice,it turns into water.如果你把冰加热，它就会化成水。2.If you drop the glass on the floor,it breaks.如果你把玻璃杯摔落在地上，它就会破碎。的的反义词反义词：=unless,“如果不，除非如果不，除非”I wont go there unless I hear from you.(同义句同义句)I wont go there _ I _hear fr
19、om you.if dont I wont go to the party if I am not invited.(同义句同义句)I wont go to the party_ I am invited.unless变换：变换：1.有有 引导的引导的条件状语从句条件状语从句的复合句中，当主句和从句的的复合句中，当主句和从句的主语均为主语均为you时，可转换为时，可转换为“祈使句，祈使句，and+简单句简单句”或或 “祈使句，祈使句，or+简单句简单句”You can pass the exam if you work hard.-，and you will pass the exam.If
20、you dont hurry up,you will be late again.Hurry up,-you will be late again.Work hardor2.借助介词借助介词with 或或without来转换。来转换。例如例如:If you help me,Ill finish my job soon.-,Ill finish my job soon.如果你帮我，我将很快完成我的工作。如果你帮我，我将很快完成我的工作。If there is no water,fish may die.Fish may die -.如果没有水，鱼可能会死。如果没有水，鱼可能会死。With you
21、r helpwithout water变换：变换：引导的引导的条件状语从句条件状语从句与与 引导的引导的宾语从句宾语从句的区别的区别if?Do you know the meaning of.是否If 在在宾语从句宾语从句中翻译为中翻译为“是否是否”在在中翻译为中翻译为“”Ill go to see you if I am free next week.I want to know if he is a teacher.whether1.if 在句中的含义不同在句中的含义不同 引导的引导的条件状语从句条件状语从句与与 引导的引导的宾语从句宾语从句的区别的区别2.if 在从句中的位置不同在从句中
22、的位置不同If 引导的引导的宾语从句宾语从句放在主句之放在主句之后后；if引导的引导的可放在主句之可放在主句之也可放在主句之也可放在主句之后后 用用”，“隔开隔开=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.1.Can you tell me if she can come to the meeting?2.She will not go there if it is rainy tomorrow.3.
23、I cant guess if she will be angry.4.If we help each other,we both will get good results.引导的引导的条件状语从句条件状语从句与与 引导的引导的宾语从句宾语从句3.时态要求上有区别时态要求上有区别 引导条件状语从句的时态为一般现在时引导条件状语从句的时态为一般现在时 记住记住“主将主将从现从现”1.I wanted to know if there a sports meeting next month.doesnt rainwould be2.If it ,well hold it.If 引导的引导的宾语从
24、句宾语从句的时态由主句及本身时的时态由主句及本身时态决定态决定1.if 在句中的含义不同在句中的含义不同2.if 在从句中的位置不同在从句中的位置不同3.时态要求上有区别时态要求上有区别明白吗明白吗 引导的引导的条件状语从句条件状语从句与与 引导的引导的宾语从句宾语从句的区别的区别1.He will help me with my maths if he _ free.A was B will be C would be D is2.I dont know_ he will come tomorrow._ he comes,Ill tell you.A if;Whether B whether
25、;Whether C if;That D if;If3.Please tell her my telephone number if she _(want)to know.wantsDD8.-Would you please tell me_ next?-Think it over.Youll find a good way.A when to do B how to do C what to do D where to do9.I dont know if my uncle _.If he _,I will be very happy.A comes;will come B will com
26、e;will come C comes;comes D will come;comes10.Either you or I _ going to Shanghai.Only one person may go there.A are B were C am D was CDC()11.If it _ sunny tomorrow,I _ boating.A.is go B.will be,go C.is,will go D.will be,will go()12.-what will you do if it _ tomorrow,-Ill stay at home and watch TV.
27、A.rain B.rains C.will rain D.is raining CB()13.If he _,I _ him the time.A.comes,tell B.will come,will tellC.comes,will tell D.will come,tell()14.If it _,it _cold.A.snows,will be B.snows,isC.will snow,will be D.will snow,is()1 5.If you _a stone into water,it _.A.put,sinks B.put,will sinkC.will put,sinks D.will put,will sinkCB A
