If引导的条件状语从句

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if 条件状语从句

if引导的条件状语从句引导条件状语从句最常用的连词是if，常见的if条件状语从句表示在某条件下，某事很可能发生，条件是可能存在的，主句中某种情况发生的概率也是很高的。

如：一，第一类：1）表示普遍真理和客观事实：If you heat ice ,it melts .If you pour oil on water,it floats.不受时间限制的自然法则的条件句，主句，从句都是一般现在时。

2）表示习惯性的动作If I make a promise , I take it .If it rains ,I go to work by car.表示一个现在习惯性的动作，主句和从句的谓语动词都是一般现在时。

3）表示过去的习惯性，经常的动作If it rained,I went to work by car.If I was hungry, I usually had a full meal.主句和从句谓语动词要依据时间来变为一般过去时。

questions and answers :What do you like to drink if you are very thirsty?How many days are there in February it it is a leap year ? Who do people go and see if they get ill ?第二类：If we catch the 10 o’clock train ,we shall (will ,can,may,must ,should ) get there in time .If it is fine tomorrow ,we can have a picnic somewhere.If you wake up before me , give me a call .条件句（从句）用一般现在表示将来，主句用shall 加动词原型或者是祈使句在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。

if 条件状语从句

If 引导的条件状语从句If 引导的条件状语从句表示“如果… , 假如…”，表示在某种条件下某事可能发生。

含有if引导的条件状语从句的复合句由主句和从句构成。

If引导的是完整的句子，一定要有主语，称为从句，另一个句子称为主句。

句子结构：1. 祈使句/ 主句（will do ）/ 主句（can / must / should 等+do）+if条件状语从句2. if条件状语从句, + 祈使句/ 主句（will do ）/ 主句（can / must / should 等+do）1. Drop in on me if you have time . = If you have time , drop in on me .2. I will help you do housework if I finish my homework earlier .= if I finish my homework earlier , I will help you do housework .3. Y ou must study hard if you want to pass the exam . = If you want to pass the exam , you must study hard .特别注意：（1）上述情况下，条件状语从句必须用一般现在时态表示将来动作。

不可用一般将来时。

（2）if条件句和”祈使句+and / or+简单句”句型的转换Hurry up , or you’ll be late .= If you don’t hurry up, you will be late .Go straight ahead , and you will find the post office . = If you go straight ahead , you will find the post office .(3) unless 引导条件状语从句，可以和if转换。

If引导的条件状语从句

If引导的条件状语从句在复合句中，由从句表示的状语叫做状语从句。

从句由连接词if或unless=(if not)引导的状语从句叫做条件状语从句。

条件状语从句最常用的连词是if（if是从属连词，译成：如果，假如，倘若）,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。

例句：If people obey the traffic rules, ➜从句there will be fewer accidents. ➜主句结构：if引导的条件状语从句，既可以放在主句之前也可以放在主句后。

（放在主句前时，要用逗号隔开。

）原句可改为：There will be fewer accidents if people obey the traffic rules.主将从现，主情从现，主祈从现，If it rains tomorrow, I will stay at home.If you are hard-working, your parents may feel happy.Study hard, if she wants to get good grades.If引导的条件状语从句和宾语从句的区分：（if的含义不同）I.填空1. I will watch TV every day. My mother will be angry.If I ________TV every day, my mother _____ _____angry.2. He will have a strange haircut. The teachers won’t agree.If he _____ a strange haircut, the teachers______ _______.II. 选择1.If it rains tomorrow, we _____ visit the museum.A. don’t do B .won’t goC .aren’t go D. didn’t go.2. Will you go to the park if it ____ fine?A. will beB. wasC. is D /3. If you __to school late, your teacher _____ angry with you.A. come; areB. come, will beC. will come; areD. will come; will be4. If you _____ hard, you will ___ successful.A. work, areB. works, isC. to work, beD. work, be5. If I ____ too much TV, my mother will _______.A .watch, angryB .watched, be angryC .watch, be angryD .will watch, be angryⅢ.翻译句子:1.如果你起床晚了, 你就会上学迟到。

If引导的条件状语从句

If引导的条件状语从句很多英语学习者都觉得If引导的条件状语从句这个句型很难，学习起来很吃力。

下面是店铺为你整理的If引导的条件状语从句的相关资料，希望大家喜欢!If引导的条件状语从句用法1.if引导的条件状语从句可以放在主句之前，也可以放在主句之后，如果放在主句之前，中间要用逗号将主句和从句隔开。

例如：If I am free, I will come to see you.= I will come to see you if I am free.如果我有空，我就来看你。

2. 在含if引导的条件状语从句的复合句中，主句用一般将来时，从句通常用一般现在时态表示将来意义，即“主将从现”原则。

例如：If it snows tomorrow, we will go skiing.如果明天下雪，我们就去滑雪。

3. 在含if引导的条件状语从句的复合句中，语句的谓语还可含有情态动词can、must、may等，主句也可是祈使句。

例如：If it stops raining, we can go out.如果雨停了，我们就能出去。

4. 在含if引导的条件状语从句的复合句中，如果主句部分描述的是客观事实或真理，要用一般现在时。

例如：If you heat the ice, it turns into water.如果你加热冰，它就会变成水。

if引导的非真实条件句对过去的虚拟条件从句(if):主语+had done 主句might/would/should/could+have done对现在的虚拟if+ 主语+动词过去式(be用were)主句might/would/should/could+do对将来的虚拟if+主语+动词过去式(be用were)或主语+should do或主语+were to do主句 might/would/should/could+doe.g.Tom got to the station in time because he started earlier.If Tom had started late, he would have missed the train.Do you think the thief entered through the door?No, if he had, I don't believe, he would have broken the living room window.If the book weren't so expensive, I would buy it.If you didn't live so far away, we would be able to visit you more.What would you do if you lost your passport in a foreign country?Why hasn't he come? If he should not come on time, we would have to put off the trip.2.注意事项e.g.If she hadn't work hard at English in the past, she wouldn't work as well as a secretary in a large company now. 混合时间的虚拟语气从句为对过去的虚拟，主句是现在。

if引导的条件状语从句总结(精)

if引导的条件状语从句总结(精)if引导的四种条件状语从句一、零条件句/绝对真实条件句(Zero Conditional)零条件句，又叫绝对真实条件句，用于阐述事实。

用来表达在该条件下，结果一定会如此(如规则，客观规律、真理等)。

结构是：If+主语+do/does，主语+do/does。

其从句和主句的谓语动词通常为一般现在时。

二、第一条件句/相对真实条件句(First Conditional)第一条件句又叫相对真实条件句，谈论将来可能发生的事情，并考虑这件事情的结果。

强调偶然性或一次性的条件，也可以与绝对真实条件句同义。

if从句用一般现在时或其他现在时，表示将来可能发生的事情(条件);主句用一般将来时，表示这件事情的结果。

结构是：If+主语+do/does，主语+will do。

三、第二条件句/现在虚拟条件句(Second Conditional)第二条件句是虚拟条件句的一种，即现在虚拟条件句(Unreal Present)，用来表达在现在或将来时间下不太可能或不可能发生的条件，这种条件句还可以用来表示试探性的、委婉的语气(可以理解为不大有自信，所以不太真实的条件)。

结构是：①与将来事实相反的非真实条件句是If+主语+should do/were to do/did，主语+would/should/could/might do;②与现在事实相反的非真实条件句是If+主语+did，主语+would/should/could/might+do。

四、第三条件句/过去虚拟条件句(Third Conditional) 第三条件句是表示与过去事实相反的虚拟语气，是用来表达如果(If)当时那样发生，另外一方面(当时)结果会如何。

通常是指过去的事情，带有一切已经太迟而不能够补救的意思。

结构是：If+主语+had done，主语+would/should/could/ might+have done。

if 条件句的时态搭配1.if从句用一般现在时，主句用一般将来时2.if从句用一般现在时，主句用may/might/canIf the fog gets thicker the plane may/might be diverted.3.if从句用一般现在时，主句用must/shouldIf you want to lose weight you must/should eat less bread.4.if从句用一般现在时，主句用一般现在时5.if从句用现在进行时，主句用一般将来时6.if从句用现在完成时，主句用一般将来时If you have finished dinner I’ll ask the waiter for the bill.。

If-引导的条件状语从句

If 引导的条件状语从句If 引导的条件状语从句遵循主过从过、主将从现的原则。

主将从现（主情从现、主祈从现）If it rains tomorrow,I won’t climb the hills.If it doesn’t rain tomorrow,I will go to the countryside with my friends.If 引导的条件状语从句If 引导的条件状语从句遵循主过从过、主将从现的原则。

主将从现（主情从现、主祈从现）If you will help me,I'll finish it on time.We may go out if it's fine tomorrow.If you finish your homework,you can watch TV.Please call me if you go shopping next Sunday.If I go there，I'll take her some flowers.We'll stay at home if it rains tomorrow.Please call me if he’s at home.If you work harder,you’ll pass the exam.She will visit her grandpa if she has time tomorrow.We’ll take a taxi to the city if the train doesn’t arrive on time.The teacher will be angry if he is late.If引导的条件状语从句与unless引导的条件状语从句的转换If+否定形式=unless+肯定形式You won’t pass the exam if you don’t work hard.=You won’t pass the exam unless you work hard.If you don’t go to bed earlier,you will feel tired in the morning. =Unless you go to bed earlier,you will feel tired in the morning. If it doesn’t rain,he will play with me tomorrow.=Unless it rains,he will play with me tomorrow.If she doesn’t come,I’ll go shopping alone=Unless she comes,I’ll go shopping alone.if条件状语从句与祈使句,and/or＋一般将来时的句子转化If you get up early,you’ll get there on time.=Get up early,and you’ll get there on time.=Get up early,or you won’t get there on time.If you get up early，you won't be late for school.=Get up early，and you won't be late for school.=Get up early，or you will be late for school.If you don’t get up early,you won’t catch up with the early bus. =Get up early,and you will catch up with the early bus.=Get up early,or you won’t catch up with the early bus.if条件状语从句与without的句子转化If there is no water,we can't live.=We can't live without water.If there is no water,fish will die.=Fish will die without water.If you help me,I’l l finish the work soon.=With your help,I finish the work soon.if条件状语从句与祈使句,and/or＋一般将来时的句子转化If you get up early,you’ll get there on time.=Get up early,and you’ll get there on time.=Get up early,or you won’t get there on time.If you get up early，you won't be late for school.=Get up early，and you won't be late for school.=Get up early，or you will be late for school.If you don’t get up early,you won’t catch up with the early bus.=Get up early,and you will catch up with the early bus.=Get up early,or you won’t catch up with the early bus.1. your friend ,I'll tell you.eB.will comeesD.are coming2. If you go to college，you a good education.A.will getB.getC.getsD.got3.I want to know if they tomorrow.eB.will come C comes D.came4.Take enough exercise, you'll be in good heath.A.orB.soC.butD.and5.If it (not rain),he (play)basketball withme tomorrow.6.If Uncle Lan ______(come),I______(call)you up.7.She must see a dentist if she______(have)a toothache.8.Please wake me up if he______(come)back.9.Hurry up！Or you ______(be)late again.10.If you don’t be quick,you(be)late.1.We won’t wait for you you can’t arrive on time.A.untilB.whenC.afterD.if2.The children will go to the zoo if it (not rain)this Saturday.3.If she work hard,she be able to go to colleage.A.not,notB.won’t,won’tC.won’t,doesn’tD.dpesn’t,won’t4.If I run every day,I (be)healthier.5.If it (not rain),he (play)with me tomorrow.6.She must see a dentist if she (have)a toothache.7.Study hard,or you (not pass)the test.8.If you (not go)to bed earlier,you will feel tired in the morning.9.If he (be)free tomorrow,he will come to your birthday party.10.We will go to the zoo if it (not snow)tomorrow.。

if引导的条件状语从句造句

if引导的条件状语从句造句
1. If it rains tomorrow, we will stay at home.如果明天下雨，我们就待在家里。

2. I will help you if you ask me.如果你问我，我会帮助你。

3. If she studies hard, she will pass the exam.如果她努力学习，她会通过考试。

4. We can go to the park if the weather is nice.如果天气好的话，我们可以去公园。

5. If you need any assistance, just let me know.如果你需要任何帮助，告诉我就可以了。

6. I will go for a walk if I finish my work early.如果我早早完成工作，我就会去散步。

7. If they invite us, we will definitely attend the party.如果他们邀请我们，我们一定会参加聚会。

8. If you don’t eat breakfast, you will feel tired later.如果你不吃早餐，稍后会感到疲倦。

9. If he keeps practicing, he will become a great musician.如果他继续练习，他会成为一位出色的音乐家。

10. If you save enough money, you can travel next year.如果你存够钱，明年就可以旅行。

if引导的条件状语从句主句从句

if引导的条件状语从句主句从句
1. If it rains tomorrow, we will cancel the picnic.
如果明天下雨，我们将取消野餐。

2. I will help you with your homework if you ask me nicely.
如果你好好请求我，我会帮你做作业。

3. If you study hard, you will pass the exam.
如果你努力学习，你就会通过考试。

4. She will go to the party if she finishes her work on time.
如果她按时完成工作，她会去参加聚会。

5. If you don’t hurry, you will miss the bus.
如果你不快点，你会错过公交车。

6. We can go for a hike if the weather is nice.
如果天气好，我们可以去远足。

7. If he apologizes, I will forgive him.
如果他道歉，我会原谅他。

8. You will succeed if you believe in yourself.
如果你相信自己，你会成功。

9. If they invite us, we will definitely attend the wedding.
如果他们邀请我们，我们一定会参加婚礼。

10. If you keep practicing, you will improve your skills.
如果你继续练习，你会提高你的技能。

if引导的四种条件状语从句

if引导的四种条件状语从句1. If it rains tomorrow, I won't go out. For example, imagine you planned a picnic, and then it starts raining. Wouldn't you be a bit disappointed and change your plans?2. If I have enough money, I'll buy that dress. Like, you see something you really love but don't have the cash, how frustrating is that?3. If she comes here, I'll be so happy. Just think, if that special person shows up, won't your heart just leap with joy?4. If he doesn't study hard, he won't pass the exam. You know, it's like building a house without a solid foundation, it's bound to collapse.5. If we leave now, we can catch the movie. Say, you really want to see that movie and you know if you don't hurry, you'll miss it.6. If they invite me, I definitely will go. Isn't it great when you get invited to something you really want to do?7. If I win the lottery, I'll travel the world. Imagine being able to go anywhere and see all those amazing places.8. If she doesn't apologize, I won't forgive her. You know how itfeels when someone wrongs you and doesn't say sorry?9. If he keeps being lazy, he'll never achieve his goals. It's like trying to run a race while sitting down!10. If we work together, we can achieve great things. Just like a team pulling together to win a championship.My view is that these if clauses really show how different choices and situations can lead to different outcomes. They make us think about what might happen and how we would react.。

用if引导的条件状语从句15个

用if引导的条件状语从句15个如果引导的条件状语从句是英语语法中非常常见的句型，用于表达某种条件下发生的情况。

下面将介绍15个以if引导的条件状语从句的相关内容。

1. **Zero Conditional**Zero conditional用于表达普遍真理或习惯性的动作，结构为if + 现在时，现在时。

例如：If you heat water to 100 degrees, it boils.2. **First Conditional**First conditional用于表达将来可能发生的事情，结构为if + 现在时，将来时。

例如：If it rains tomorrow, we will stay indoors.3. **Second Conditional**Second conditional用于表达与现在事实相反的假设，结构为if + 过去时，would/could/might + 原形动词。

例如：If I were rich, I would travel around the world.4. **Third Conditional**Third conditional用于表达与过去事实相反的假设，结构为if + 过去完成时，would/could/might + have + 过去分词。

例如：If I had studied harder, I would have passed the exam.5. **Mixed Conditional**Mixed conditional结合了第二和第三条件句的结构，用于表达过去的假设对现在的影响，或现在的假设对过去的影响。

例如：If I had known you were coming, I would have baked a cake.6. **Unless**Unless的意思是“除非”，引导的条件状语从句表示否定条件。

结构为unless + 句子，相当于if not。

总结好的：IF引导的条件状语从句

if引导的条件状语从句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“构　成条件从句主句时　态If＋一般现在时主语＋shall/will+动词原形例　句If he comes,he will take us to the zoo.1)用法：(1)条件状语从句通常由连词if引导，意为“如果、假如”，主句不能用be going to表示将来，而应该用shall，will。

If you leave now, you are never going to regret it. (错误) If you leave now, you will never regret it. (正确)(2)if “如果”，引导条件状语从句，主句用一般将来时，从句则用一般现在时，如： If it rains tomorrow, I shan’t climb the hills.(3)另外，主句是祈使句或含有情态动词，从句也用一般现在时。

如：Please call me if he comes next Sunday.Can you call the policeman if you are in the trouble.注意宾语从句中的if与条件状语从句if的区别。

宾语从句中的if“是否”相当于whether，引导宾语从句，时态需根据语境确定。

如果主句用一般现在时，从句可以根据具体情况选用时态，如果主句用一般过去时，从句必须用过去式的某种形式。

I don't know if it will rain tomorrow. 我不知道明天是否会下雨。

Our teacher said there was going to be a football match the next month.我们说下月将有场足球比赛。

【边学边做】用括号内所给词的正确形式填空。

1. What will you buy if you ________（have）a lot of money?2. If it ________（not snow）tomorrow, we will feel unhappy.3. You mustn’t go to school if you ________（be）still in bed.4. If he _______（be）at home at that time, he would know it.5. Please show me the way if you ________（know）it.6. You will hurt your teeth if you ________（eat）too much candy.7. If you gave me a toy car, I _________（be）very happy.8. I would get the prize if I _________（work）hard.9．If she ______ (finish ) work early ,she ______(go) home.10．If the weather______（be）fine，we_______(go)for a walk .11. If I_____(have) time tonight ,I _______(finish) the book I’m reading.12. If it ______(rain) next weekend , we_______(not be able to ) plant the vegetable .13. If it_______(rain),we______(stay) at home .14.If she______(arrive) ,she _____(phone) me .15. If he_____(call),tell him I’ll ring back .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 PekingUniversity.二、完成句子1. 他如果看电视太久了，他的父母会不高兴。

If引导的条件状语从句

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4
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. Work hard ----------------，and you will pass the exam.
for you , it will be good for your study.
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5. If you __d_o_n_’_t _w_o_rk___(not work ) hard , you _w_o_n_’_t _p_as_s_(not pass) the exam.
6. If she __m__e_n_d_s_(mend) the computer , her father __w_o_n_’t_b_l_am__e_(not blame ).
W--i-t-h--y--o-u--r--h--e-l-p-, I’ll 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 w--i-th--o--u-t--w--a--t-e-r--. 如果没有水，鱼可能会死。
I won’t go there unless I hear from you.(同义 if 句) don’t
I won’t go there _____ I _____hear from you. I won’t go to the party if I am not invited. (同义句) unless I won’t go to the party_____ I am invited.

if引导的条件状语从句的用法

（一）真实条件句，假设的条件是
（3）假设
真的，或者有可能成为真的；
（二）假设将来，假设的条
将来

件是将来可能实现的。
1. if 非真实条件句（虚拟）——假设现在
（二）遵循的原则
should do
might+do
例 7 If I _____(be) a bird,I would fly to you right
状态，是正在玩球的意思，
所以此空填 is playing。
3. if 引导的真实条件状语从句——假设将来
例 3 If it _____(rain) tomorrow,we will stay at home.
解析：如果你不想受伤，
就不要玩刀。根据 Don’
t
play with the knife,主句是祈使句，所以从句为 if 引导
to the park.
he will take me to the park,主句用的一般将来时，而且
可以分析出，他哥哥现在还没有回，所以从句为 if 引
导的表将来的条件状语从句。根据“主将从现”的原
则，此空填 comes。
2. if 非真实条件句（虚拟）——假设过去
例8
Years ago if someone_____ (turn) round to
批改学生作文时，遇到拼写错误较多的学生可以这样
及各个时代相关代表作品的赏析，感受中西方文化的
评价：
不同，提高其审美水平；在进行人教版（2014）高中英
neat and tidy！
学生参观学校的科学实验室或者本地的科技馆，感受
1. 认同欣赏:I like your handwriting，which is so

if 引导的条件状语从句

一、if 引导的条件状语从句，主句用一般将来时，从句一般现在时。

即“主将从现”连词if的意思是“如果”，它引导的句子表示某事发生所需要的条件，即“在……条件下某事才能发生”，在句子中充当状语，因此我们称之为条件状语从句。

在复合句中连词if引导的句子为从句，被修饰的句子为主句。

从句可以放在主句后，也可以放在主句前，从句放在主句前时，应用逗号将它与主句隔开if_______If you study hard, you will get good grades.I _won’t_ play basketball this afternoon if it_ __rains___.I ___will_ play basketball this afternoon if it __doesn’t_ _rain.练一练1. If you _____ to the party, you’ll have a great time.A. will goB. wentC. goD. going2. – What are you going to do tomorrow? --We’ll go to the library tomorrow if it ___.A. isn’t rainB. rainC. won’t rainD. doesn’t rain3. I’ll give the book to him if he ___ here next Sunday.A. will comeB. comesC. is comingD. came4. There _________a basketball match in our school tomorrow afternoon, if it doesn’t rain.A. will be B will have C have D is用go与rain的正确形式We_______ to the Great Wall if it ____________ tomorrow.If it ______________ tomorrow, we___________to the Great Wall.二、as soon as的用法“一···就···”的意思主句用一般将来时，从句一般现在时。

if引导的状语从句

【2011山东潍坊】 6. If Tom _____ the game, we'll give him a surpri se". A. win B. wins C. won D. miming 答案：【解析】考查if引导的条件状语从句。在if引导的条件状语从句中，如果主句和从句发生的动作都在将来时间，从句用一般现在时表将来。故选B。
5． if从句用现在进行时，主句用一般将来时 If you are looking for Peter you’ll find him upstai rs. 如果你是在找彼得，上楼就会找到他。 6． if从句用现在完成时，主句用一般将来时 If you have finished dinner I’ll ask the waiter for t he bill. 如果你吃完了，我就叫服务生来算账
if引导的宾语从句
if 引导宾语从句时，意思为：是否，从句的时态通常要和主句保持一致。 I want to know if he lives there. 我想知道他是否住在那儿。 He asked me if I could help him. 他问我是否能帮他。
【考查点】if、whether引导的宾语从句的区别
3. 只能用whether的情况在动词不定式之前只能用 whether： I can’t decide whether to stay. 我不能决定是否留下。在whether …or not 的固定搭配中： I want to know whether it’s good news or not. 我想知道它是不是好消息。在介词后，只能用whether： His father is worried about whether he loses his work. 他的父亲担心他是否会失去工作。用if会引起歧义时： Could you tell me if you know the answer? 这句话有两种意思： “你能告诉我你是否知道答案吗？”或“如果你知道答案，请告诉我，好吗？”。如用whether则可避免歧义。

if+引导的条件状语从句

一．引导条件状语从句最常用的连词是if，常见的if 条件状语从句表示在某条件下，某事很可能发生，条件是可能存在的，主句中某种情况发生的概率也是很高的。

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。

If you have finished the homework, you can go home．如果你作业做完了就可以回家了。

二．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，表示对现在或过去的一种假设。

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．要不是交通堵塞，我本会来得早一些。

另外你还要注意if 条件句的时态搭配1．if 从句用一般现在时，主句用一般将来时If he runs he’ll get there in time.如果他用跑的，他就会及时赶到那儿。

The cat will scratch you if you pull her tail.如果你拉猫的尾巴，它就会抓你。

2．if 从句用一般现在时，主句用may/might/canIf the fog gets thicker the plane may/might be diverted.如果雾在大一些，飞机可能就会改在别的机场降落。

If it stops snowing we can go out.如果雪停了，我们就可以出去。

3．if 从句用一般现在时，主句用must/shouldIf you want to lose weight you must/should eat less bread.如果你想减肥，你必须少吃面包。

if引导的条件状语从句用法

if引导的条件状语从句用法
条件状语从句是由if引导的从句，用于表达条件的情况。

在使用
条件状语从句时，需要注意以下几点：
1.结构：条件状语从句一般由if引导，后面跟着主句。

主句可以
通过if从句的情况来说明结果或者后果。

例子：If it rains, we will stay indoors.（如果下雨，我们
就会呆在室内。

）
2.时态：如果条件状语从句描述的是将来的情况，通常将来时态
在条件从句中使用，而在主句中使用一般将来时。

例子：If you study hard, you will pass the exam.（如果你
努力学习，你就会通过考试。

）
3.虚拟语气：在条件状语从句中，如果描述的是与事实相反或不
可能实现的假设，通常使用虚拟语气。

例子：If I were rich, I would buy a big house.（如果我有钱，我就会买一栋大房子。

）这里的"If I were"是对现实情况的假设。

拓展：
除了用于条件从句中，if还经常用于其他类型的从句，如时间状
语从句（if引导的时间状语从句常用于表示"每当"或"如果"的意思）、方式状语从句（if引导的方式状语从句可以表示一种条件或介绍某种
方式，例如"If possible"表示"如果可能的话"）等。