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单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,.,*,初中英语,if引导的条件状语从句,主讲人：xx,单位：正定县北早现乡,1,.,eg:,如果我有足够的钱，我就去环游世界,If,引导条件状语从句,定义：,if,“,如果,假如,”,它引导的句子表示某事发生所需的条件，即,“,在,条件下，某事才能发生”，在句子中充当状语，因此称之为条件状语从句。,If I have enough money,I will travel around the world,orI will travel around the world if I have enough money,2,.,_,if Im ill.,I will see a doctor,Look and say,If Im late,_.,I will say sorry,位置：从句可放在主句之前或之后，但是放在主句之前须有逗号隔开,3,.,If it rains tomorrow,I_.,will watch TV at home,If it _ tomorrow,_.,hell play basketball,doesnt rain,I wont_.,play basketball,4,.,I will,_,if Im hungry.,I will,_,if Im tired.,Look and say,eat some food,have a rest,5,.,位置,：,从句可放在主句之前或之后，但是放在主句之前须有逗号隔开,6,.,If,条件句：,条件句用于陈述语气，表示假设的情况可能发生，,其中,if,是,“,如果,”,的意思。,主句,一般将来时,，从句用一般现在时。,7,.,用法：,1.,如果主句是一般将来时，从句则用一般现在时。,If it rains,（从句），,I will stay at home.,Ill go with you if you dont want to go alone,（从句）,.,2.,如果主句含有,must,may,can,等情态动词，从句也要用,一般现在时。,If you drive too fast,you may have an accident.,You must stop if the traffic is red.,If you,finish,the homework,，,you,can go,home,如果你作业做完了就可以回家了。,If you,want,to lose weight you,must/should eat,less bread.,如果你想减肥，你必须少吃面包。,8,.,3.如果主句是祈使句，从句同样要用一般现在时。,Dont go and play football if you dont finish your homework.,Please call me if he comes next Sunday.,9,.,练一练：,1,。如果她早点儿起床，就有时间在家里吃早餐,If she_ _a little earlier,shell have time to eat,breakfast at home.,2,。如果你参加聚会，你将会过得很开心。,If you_ the party,you_ _ a great time.,3,。如果明天下雨，我们将不去野餐,If it _tomorrow,we _ _ for a picnic.,4,。如果你经常听英文歌，你将会喜欢英语,If you often _ _English songs,you_ _English.,10,.,11,.,语法：,例句,If I have enough money,I will travel around the world,：,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,I will travel around the world if I have enough money.,.,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,：,12,.,13,.,主句谓语中也可以含有情态动词，如：must,can,could,should等,时态,：,if引导的条件状语从句，,主句用一般将来时（will）,从句用一般现在时。,例句,：,If,people obey the traffic rules,there,will,be,fewer accidents,.,主句谓语中也可以用had better(not)do,提建议,例句,：,如果交通指示灯是红的，你必须停下来等一等。,eg:If the traffic lights are red,you must stop and wait.,例句：如果你想减肥，你最好锻炼。,eg:If you want to lose weight,you had better take some exercise.,“主将从现”,14,.,if的反义词：if.not.=unless,意思是：“如果不，除非”,I wont go there unless I hear from you.(同义句),I wont go there _ I _hear from you.,if dont,I wont go,to the party if,I,am not invited.,(同义句),I wont go,to the party,_,I,am invited.,unless,15,.,变换：,1.有if引导的条件状语从句的复合句中，当主句和从句的,主语均为you时，可转换为“祈使句，and+简单句”或,“祈使句，or+简单句”,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 hard,or,16,.,2.,借助介词with 或without来转换。,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。,If there is no water,fish may die.,Fish may die -.,如果没有水，鱼可能会死。,With your help,without water,17,.,注意事项,1.在if引导的条件状语从句中，当主句是一般将来时时，不能够使用be going to结构，而要用will。,例如：Ill help you with your English if I am free tomorrow.如果明天我有空，我会帮你学英语。,2.在if引导的条件状语从句中不能够使用some，而要用any。,例如：If you have any questions to ask,please come to my office.如果你有问题要问的话，请到我办公室来。,18,.,练习：,1、如果明天下雨，我就和同学们去野餐。,2、如果你起来晚了，你上学将迟到。,3、如果你想节约能源，你最好骑自行车。,4、如果朋友有麻烦，我们应该尽力帮助他们。,19,.,See you!,20,.,
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