If sentencesIf 引導(dǎo)的條件狀語從句引導(dǎo)的條件狀語從句1公開課If you cool water,it turns into ice.if clause從句從句main clause主句主句2公開課 1.If you heat metal,it melts.如果把金屬加熱，它就會融化如果把金屬加熱，它就會融化。2.Water turns into ice if you cool it.如果你冷卻水，它就會變成冰如果你冷卻水，它就會變成冰。if clause從句從句main clause主句主句從句從句主句主句從句從句主句主句從句在主句前時，從句在主句前時，_ （用（用/不用）逗號隔開不用）逗號隔開當(dāng)主句在前時，則當(dāng)主句在前時，則_（用（用/不用）逗號不用）逗號不用用3公開課If you drop a glass,it breaks.If you heat ice,it melts.If you stand in the rain,you get wet.主句和從句都用主句和從句都用_(時態(tài)時態(tài))因為因為if引導(dǎo)的條件句說的是引導(dǎo)的條件句說的是_一般現(xiàn)在時一般現(xiàn)在時客觀事實客觀事實/普遍現(xiàn)象普遍現(xiàn)象4公開課Actions with definite results 讀下列例句，試著自己總結(jié)讀下列例句，試著自己總結(jié)if if 的用法：的用法：1.If you heat metal,it melts.如果把如果把金屬加熱金屬加熱，它就會融化，它就會融化。2.Water turns into ice if you cool it.如果你冷卻水，它就會變成冰如果你冷卻水，它就會變成冰。3.If you stand in the rain,you get wet.如果你站在雨里，就會淋濕。如果你站在雨里，就會淋濕。4.If you drop a glass,it breaks.如果你把玻璃杯掉在地上，它就會碎。如果你把玻璃杯掉在地上，它就會碎。5公開課 由例句我們可以知道：如果if引導(dǎo)的條件句談?wù)摰氖且环N_ 時，主句謂語動詞便不用shall/will+動詞原形，而直接用_時的動詞形式。真理真理/客觀事實客觀事實一般現(xiàn)在一般現(xiàn)在6公開課Water _(turn)into ice if you _(cool)it.If you _(stand)in the rain,you _(get)wet.turnscoolstandget7公開課1.-b2.-d3.-g4.-a5.-h6.-c7.-f8.-e8公開課1.If you _water.2.A balloon _ it.3.If you _water.4.Metal _it.5.Wood _water.6.A glass_ it.heat ice,it turns intobursts if you stick a pin into cool steam,it turns intomelts if you heatfloats if you put it intobreaks if you drop9公開課Actions with possible results 讀下列例句，總結(jié)讀下列例句，總結(jié)if if 的用法：的用法：1.If he runs,hell get there in time.如果他跑步去，就會及時趕到那。如果他跑步去，就會及時趕到那。2.He will help you if you ask him.如果你請他幫忙，他會幫你的。如果你請他幫忙，他會幫你的。3.If you fail in the exam,you will let him down.如果你考試失敗了，你會讓他失望的如果你考試失敗了，你會讓他失望的 4.If you get up late,you will be late for school.如果你起床晚了，上課就會遲到。如果你起床晚了，上課就會遲到。10公開課 由例句我們可以知道：在if 引導(dǎo)的條件狀語從句中，如果從句談?wù)摰氖且粋€有可能發(fā)生的事實有可能發(fā)生的事實以其產(chǎn)生的相關(guān)結(jié)果，從句用_,主句用_.一般現(xiàn)在時態(tài)一般現(xiàn)在時態(tài)一般將來時態(tài)一般將來時態(tài)(主將從現(xiàn)主將從現(xiàn))11公開課I _(stay)at home if it _(rain)tomorrow.If he _(not come),I _(go)swimming alone.will stayrainsdoesnt comewill go12公開課If you get up late,you will be late for school.get up latelate for school13公開課If the telephone rings,I will answer it.ringanswer14公開課If I have a lot of money,I will buy a big house.a lot of moneya big house15公開課hard-workingIf she is hard-working,she will get good grades.get good grades16公開課go fishing.If it is sunny this Sunday,Ill go fishing.sunny this Sunday17公開課P105 B William has five problems Give him some advice from column A and B 1 I sometimes forget to take the right book to school.If you check your timetable every night,youll know which books to take.18公開課一、判斷正誤，如果有誤，請更正一、判斷正誤，如果有誤，請更正1.If you will do more exercise this summer,you will be very fit.2.The candle burns,if you light it.will do do把逗號去掉把逗號去掉19公開課3.I will build many schools for the poor children if I win a billion dollars.4.If you freeze water,it will turn into ice.5.My uncle visits the museum if he will have time.正確正確will turn turnsvisits will visit,will have has20公開課If 的兩個意思:If:“如果如果”“是否是否”引導(dǎo)條件狀語從句引導(dǎo)條件狀語從句引導(dǎo)賓語從句引導(dǎo)賓語從句I dont know if he will come tomorrow.I will go to the cinema if it doesnt rain.主現(xiàn)從現(xiàn)主現(xiàn)從現(xiàn)/主將從現(xiàn)主將從現(xiàn)if可用將來時可用將來時21公開課Betty will visit the History Museum if it _(rain)tomorrow.Ben wants to know if it_(be)fine tomorrow.If 引導(dǎo)的條件狀語從句不用將來時，意思為“如果”。If 引導(dǎo)的賓語從句可以用將來時，意思為“是否”。doesnt rainwill be22公開課Exercises: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;Whether C if;That D if;If3.Please tell her my telephone number if she _(want)to know.wantsDD23公開課4.Will you come and stay with us for a while if you _(finish)doing your homework?5.Wang doesnt know if there _(be)an English evening next week.6.Mike asked me if we _(ask)any questions the next class.7.We are going for picnic tomorrow.Ill call Wendy to make sure_.A why to start B when to start C what to start D which to startwould askfinishwill beB24公開課8.-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 come;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 CDC25公開課()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.A.rain B.rains C.will rain D.is raining CB 26公開課()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 27公開課11.He_(help)me with my maths if he _(be)free.12.I dont know if Jim _ tomorrow.If he _,I will be very glad.(come)13._(tell)her my telephone number if she _(want)to know.14.If it _(be)sunny tomorrow,I _(go)boating.15.If you _(boil)water,it _(turn)into steam.16.You can _(travel)around the world if you _(have)money.will helpiswill comecomesTellwantsiswill goboilturnstravelhave28公開課Translate the following sentences:1.如果你請他幫忙,他會幫你的。If you ask him,he will help you.2.如果你考試不及格,你會讓他失望的。If you fail in the exam,you will let him down.3.如果你作業(yè)做完了就可以回家了。If you have finished the homework，you can go home4.如果熊陷入危險，它們就攻擊人。If bears are in danger,they attack people.5.如果我早早地到那里，我就可以快點看病。If I get there early，I can see the doctor quickly.29公開課 翻譯下面句子。1.如果明天不下雨的話，我就和同學(xué)們?nèi)游飯@。2.如果周六你去購物的話，我就去。If it doesnt rain tomorrow,I will go to the zoo with my classmates.I will go shopping on Saturday if you go.30公開課3.如果可能的話，我就去火車站接你。4.如果你想減肥，就鍛煉身體吧。If possible,Ill meet you at the railway station.Take some exercise if you want to be thinner/lose weight.31公開課