初中英语——If引导的条件状语从句(整理版)说课讲解

学习目标：1、了解并掌握if引导的条件状语从句的意思2、了解并掌握if引导的条件状语从句的位置3、了解并掌握if引导的条件状语从句的用法一、if引导的条件状语从句的意思如果....，就....二、if引导的条件状语从句的位置有几种情况1、if you go to London, make sure you visit the Science Museum.2、She will go to America for English study if Mary passes the exam.3、If it rains tomorrow, we will have a picnic next week.4、Work hard if you want to succeed.5、He thinks it will go wrong if I play games on it.分析一下结构：____________________________________________________________________________练习：判断下列句子的主从句1.if you go to London, make sure you visit the Science Museum.2.She will go to America for English study if Mary passes the exam.3.If it rains tomorrow, we will have a picnic next week.4.Work hard if you want to succeed.5.He thinks it will go wrong if I play games on it.三、if引导的条件状语从句的用法(A)1.If you ever go to London, make sure you visit the Science Museum.2.Work hard if you want to succeed.3.If you don’t like watching TV, reading a book.4.Put on some warm clothes if the weather gets colder.5.If you do not feel well, please go to see the doctor.总结：______________________________________练习：1.If you _________(want) to see old machines _________(go) to museum.2.If you _________(visit) London,_________(take) a boat trip on the river.3.If the computer does not _________(start) immediately,_________(wait) for one minute.4.If the weather_________(get) colder,_________(put) on warm clothes.5.If any student_________(have) a high fever,_________(send) him/her to the school doctor at once.6.If you_________(want) to know how it works,_________(read) the book.(B)1.If I start after dinner, I’ll finish it before I go to bed.2.If you do all these other things, you won’t have time to study.3.If you offer to do some housework, he will realise that you are very sorry.4.He thinks it will go wrong if I play games on it.总结：____________________________________________________________________________Join the sentence with if.例：Listen in class, or you will not understand what to do.→If you do not listen in class, you will not understand what to do.1.Eat breakfast, or you will get hungry at school._____________________________________________________________________ 2.Hurry up!You will be late._____________________________________________________________________ 3.Read the book carefully.Then you will not make mistakes._____________________________________________________________________ 4.Don’t watch too much TV, or your eyes will hurt._____________________________________________________________________ 5.Work harder! You will get higher marks._____________________________________________________________________练习：用所给动词的适当形式填空。

初二英语试讲――if引导的条件状语从句40分钟示范模板（知识讲解+课堂练习+课后作业）学习目标：掌握If引导的条件状语的用法。

第一部分知识要点（ 10分钟）1.先带领学生复习学习" if " 引导的条件状语从句的用法, 然后老师给出口诀：（举例子3分钟，口诀2分钟）举例子：. 1）如果你想听音乐，就打开收音机If you want to listen to music, turn on the radio.2）如果明天不下雨，我们就出去散步。

. If it (won’t/don’t/doesn’t/ isn’t) rainy, we (will take/ take/takes) walk outside.If用法口诀：if 条件句不一般,几个要点记心间;条件句,放在前,逗号要放句中间。

条件句表可能，主句多用将来时；条件句表事实，主句常用现在时。

2. 口诀讲解（5分钟）1）主将从现在if 引导的条件状语从句中，如果从句谈论的是一个有可能发生的事实及其产生的相关的结果，主句用一般将来时态，从句用一般现在时态。

如：We can walk there if we can't find a bus .If it rains tomorrow ,we will not go to the zoo.What will you do if you find a panda in danger.2）如果if 条件句谈论的是重复发生和预示要发生的情景和事件，则主从句大多用一般现在时态。

如：If bears are in danger ,they attack people.注意：在if 引导的条件状语从句中，if 和条件句位置灵活，可直接放在主句后面，若if 条件句放句首，从句后面要加逗号，和主句隔开。

还要注意前后时态一致原则。

第二部分课堂练习（30分钟）if 条件状语从句的时态练习一．在正确的答案下划线。

条件句从句主句真实一般现在时一般将来时情态动词+动原祈使句非真实一般过去时be动词用（were）would/could+动原初中英语――条件状语从句（讲解&练习）Ⅰ条件状语从句的定义Ⅱ条件状语从句的引导词1.if引导的条件状语从句：表示在某种条件下某事很可能发生。

If we pay much attention to the earth, we'll have a better world.如果我们多关爱地球，就会拥有一个更美好的世界If it rains tomorrow, what shall we do?如果明天下雨，我们怎么办？注意：if还可以引导虚拟条件句，表示不可实现的条件，从句中多用一般过去时或过去完成时。

What would happen if there were no water ?如果没有水会怎样？2.unless引导的条件状语从句，unless的意思是如果不，除非。

可与if...not互换。

You will fail in English unless you work hard.你英语考试会不及格的，除非你更加努力。

3.as /so long as引导的条件状语从句：as /so long as意思是“只要”So long as you're happy,i will be happy.只要你高兴，我就高兴。

Ⅲ条件状语从句的种类Ⅳ条件状语从句的时态原则用法例句①主句为一般将来时态，if从句用一般现在时态（即主将从现）。

We will stay at home if it rains tomorrow.如果明天下雨，我将要呆在家。

②主句中含有情态动词，if从句用一般现在时态。

If you finish your homework, you can go home now.如果你做完了作业，你现在可以回家了。

③主句为祈使句，if从句用一般现在时态。

单元语法讲练专题语法精讲：If 引导的条件状语从句一．if引导的条件状语从句含义：条件状语从句表示主句动作发生的前提、条件、假想、推测等情况。

位置：if引导的条件状语从句可放在主句后，也可放在主句前（必须用逗号隔开）。

时态：当主句是一般将来时，从句用一般现在时表示将来。

主句从句例句主句是一般将来时从句时态应用一般现在时He will come here on time if it doesn't rain.如果不下雨，他会按时到达这儿。

主句是祈使句Please stay at home if it rains tomorrow. 如果明天下雨，请留在家里。

主句的谓语含有can,may,must等情态动词If you like,you can stay here for the weekend.你如果愿意，可以留在这里过周末。

主句的谓语是hope, wish,want等动词I want to go there if the rain stops.如果雨停了，我想去那儿。

二．if引导的条件状语从句遵循主过从过、主将从现的原则。

（1)主过从过。

If he got up earlier, he would not be late yesterday.如果昨天他早点起床，就不会迟到了。

（2)主将从现。

①If it rains tomorrow, I won't climb the hills.如果明天下雨，我就不去爬山。

②If it doesn't rain tomorrow, I will climb the hills.如果明天不下雨，我就去爬山。

（3)主祈（祈使句）从现。

Climb the hills with me if it doesn't rain tomorrow.如果明天不下雨，和我去爬山吧。

（4)主情（情态动词）从现。

If it doesn't rain tomorrow, I might climb the hills.如果明天不下雨，我可能会去爬山。

在句子中做条件状语的从句称为条件状语从句。

引导条件状语从句的连接词有：if ,unless,as/so long as，once等1.if引导的条件状语从句表示在某种条件下某事很可能发生。

If we pay much attention to the earth, we'll have a better world.如果没有水会怎样？2.unless引导的条件状语从句You will fail in English unless you work hard.3.as /so long as引导的条件状语从句So long as you're happy,i will be happy.4.once引导的条件状语从句Once you begin,never stop.提示：在条件状语从句中，用一般现在时代替一般将来时，用一般过去时代替过去将来时。

Father told me if i worked hard he would buy me a gift.if 条件状语从句的时态练习二、用所给词的适当形式填空1.If you ________(feel) tired, you _______________ (have) to have a rest.2. Where _______ he _________(see) the film if he ________________(have) time?3. If there __________(be) fewer trees, there _______________( be) more pollution.4. He _____________(dress) more casually if he ________________( not work) on weekends.5. If Marcia _____________(live) alone, she ___________________( keep) a pet parrot.6. Lana ________________( buy) a new dress if the old one ____________(be) out of style.7.The twins ______________(fight) if they_______________(argue).8. I ____________(have) a bake sale if I _____________(need) money for education.9. Peter _____________( send) me a beautiful souvenir if he ________________(tour) Spain.10. If Mr Green ___________(say) I am hard- working, my parents _________( feel) glad.11.I ____________(go) to the beach if it________________ ( not rain) this week.12. __________they __________( have) a match if the P.E. teacher _____________(be) busy?13.He ____(write) a letter to his grandparents if he ____(get) his report card this week.14. If she ____________(get) up late, she _____________ ( not catch) the early bus.15. Peter ________(major) in English if he ____(pass) the exams in Peking University.15.如果他到的晚了会发生什么事情？What _______________ if he _____________ late?16. 如果努力学习，你就会取得好成绩。

If引导条件状语从句。

在含有条件状语从句的主从复合句中，当主句谓语动词以某种形式表示将来时间概念时，条件状语从句中的谓语动词通常要用一般现在时代替一般将来时。

此句中主句为用祈使句表将来，if引导的状语从句用一般现在时。

If you see him , give him this letter .如果你见到他的话，把这封信给他。

引导条件状语从句最常用的连词是if，由if引导的条件状语从句表示在某种条件下某事很可能发生。

如：If you ask him，he will help you .如果你请他帮忙，他会帮你的。

If you fail in the exam , you will let him down .如果你考试不及格，你会让他失望的。

另外，if从句还表示不可实现的条件或根本不可能存在的条件，也就是一种虚拟的条件或假设，从句多用一般过去时或过去完成时。

如：If I were you , I would invite him to the party .如果我是你，我会邀请他参加聚会。

I would have arrived much earlier if I had not been caught in the traffic .如果没有堵车，我会到的早一点儿。

四. 课文知识点详解1. He lent me his CD recorder.他把他的CD机借给了我。

lend将某物借给某人（1）主语+lend+人+物I lent a friend a pen .（2）主语+lend+物+to+人I lent money to a friend .borrow 向某人借某物主语+borrow+物+from+人I borrowed a book from my teacher .2. If you want to send your recording by email , connect the recorder to your computer .如果你想通过电子邮件的方式发送你的录音，你要把录音连接到电脑上。

if 引导的条件状语从句（讲义）状语用来表示行为发生的时间、地点、目的、方式、程度等，通常由副词或介词短语充当，也可由一个句子充当。

I slept at home yesterday because I had a bad cold.状语从句状语从句指句子作状语。

根据其作用可分为时间、地点、原因、条件、目的、结果、让步、方式等从句。

状语从句一般由连词(从属连词)引导。

I will go to school by bike tomorrow if it is sunny.Grammar focus—I think I’ll take the bus to the party.—If you do, you’ll be late.If you take the bus to the party, you’ll be late.—I think I’ll stay at home.—If you do, you’ll be sorry.If you stay at home, you’ll be sorry.—What will happen if they have the party today?—If they have it today, half the class won’t come.—Should we ask people to bring food?—If we ask people to bring food, they’ll just bring potato chipsand chocolate.1.if 在本单元句中意为“；”，用于引导即 if 引导的是一个完整的句子，所以一定要有主谓，成为从句，另一个句子则成为主句。

If you go there, I’ll go, too.We will go hiking if it doesn’t rain tomorrow.If Bob leaves tomorrow, I will hold a party for him tonight.2.if 引导的条件状语从句既可以放在主句前，也可放在主句后。