If引导的条件状语从句.ppt

1、If引导的条件状语从句,语法：,例句：If people obey the traffic rules, there will be fewer accidents.,if引导的条件状语从句,if:从属连词，意思是：“如果，假如，倘若”,从句,主句,There will be fewer accidents if people obey the traffic rules.,原句可改为：,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。 从句位于主句之前时，常用逗号将其与主句隔开。,结构：,If it rains tomorrow, I will stay at home.,If

2、you are hard-working, your parents may feel happy.,Study hard, if she wants to get good grades.,主将从现，主情从现主祈从现，,if 引导的条件状语从句和if 引导的宾语从句的区分:,If 在宾语从句中翻译为“是否” If 在条件状语从句中翻译为“如果”,Ill go to see you if I am free next week.,I want to know if he is a teacher.,whether,1. if 在句中的含义不同,2. if 在从句中的位置不同,If 引导的宾语从

3、句放在主句之后；而if引导的状语从句可放在主句之前也可放在主句之后,= 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.,找出下列句子中哪些是if条件状语从句，哪些是if宾语从句,1. 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

4、guess if she will be angry . 4. If we help each other , we both will get good results .,3. 时态要求上有区别：口诀,If 引导条件状语从句的时态为一般现在时 记住“主将从现”,1.I want to know if there a sports meeting next month.,doesnt rain,will be,2.If it , well hold it.,If 引导的宾语从句的时态由主句及本身时态决定；,If是否，一般将来；if如果，一般现在,-Sam, do you know if Al

5、ice _to my party next week? -I think she will come if she _ free. A comes; is B will come; will be C will come; is D comes; will be,If 引导的条件状语从句的练习,1 we dont know if it _tomorrow, if it _,we wont go hiking.(snow) The sense of happiness will increase if you _ what you like to do.(do) 3 If she _(not g

6、et ) up early , shell miss the early bus . 4 be quick, please, or you will be late for school. _you _quick, you will be late for school.,1.If you _ to the party, youll have a great time. A. will go B. went C. go D. going 2 I _ her the answer if she _me. A.can tell, will ask B. will tell, will ask C. would tell, ask D. will tell, asks,C,D,3. What are you going to do tomorrow? -Well go to the library tomorrow if it _. A. isnt rain B. rain C. wont rain D. does