英语人教版八年级上册if sentence

if 条件状语从句
If I am happy I will sing
（一般现在时） （一般将来时）
she will b the party
主 将 从 现
（一般将来时）（一般现在时）
你能快速说出主句和从句吗？ Have a try ！
1.If it is rainy tomorrow，we will stay at home。 2. We will play the piano if we go to the party. 3.If she studies hard, she will get good grades 4.If he doesn’t exercise enough, he will be
sunny
rainy
cloudy
snowy
A: What will you do this weekend? B: If it is sunny this weekend, I will stay at home. What about you? C: If it is cloudy this weekend, I will watch TV. 。。。。
If you can't make a mistake,
you can't make anything.
如果你连犯错都不会，那你什么也学不会。
Nothing is difficult if you put your
heart into it. 世上无难事，只怕有心人。
Thanks for listening!
heavier. 5. I will go shopping if I am happy.
试试看，你能行

名师指导：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：If you ask him，he will help you．如果你请他帮助，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。

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，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。

专项语法讲练——if条件状语从句及其时态的用法【概念引入】英国前首相撒切尔夫人（Margaret Thatcher）曾用if条件句对男人和女人进行评价：In politics, if you want someone to make a speech, ask a man; if you want something done, ask a woman.在政治领域，如果你想要有人发表演说，那就找男士去；而如果你想真正把事情解决，那就找女士。

【用法讲解】一、概念连词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。

例如：We’ll go to the Great Wall if it doesn’t rain tomorrow. = If it doesn’t rain tomorrow, we’ll go to the Great Wall. 如果明天不下雨，我们就去长城。

二、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或will。

例如：If I’m free tomorrow, I’ll go with you. 如果我明天有空，我将会和你一起去。

2. if引导的条件状语从句，主句用一般将来时，从句则用一般现在时，即“主将从现”。

例如：If it is sunny tomorrow, I’ll climb the hill. 如果明天天气晴朗，我将去爬山。

3. 正确区分if引导的条件状语从句和if引导的宾语从句。

在条件状语从句中，if表示“如果”；而在宾语从句中，if表示“是否”。

可以用下面的方法区分：1) 从句前置法：if引导的条件状语从句，可以放在主句之前并用逗号隔开，也可放在主句之后；而if引导的宾语从句只能放在主句之后。

If 引导的条件状语从句点拨：一.if 引导条件状语从句时，为连词，意为“如果”。

句子的时态遵循“主将从现”的原则，即当主句为一般将来时，从句用一般现在时。

Eg:1. If I go to the movies, I won’t finish my homework.2. If I leave university, I’ll find a job in the city.3. If she likes it, she will read it soon.4. She won’t be late for school if she takes a taxi.5. If it doesn’t snow, he will play football with me tomorrow.6. If you don’t hurry up, you will be late again.7. If we have the party today, half the class won’t come.8. If I stay at home, I will catch the talent show.9. What will happen if your grandmother is free?10. The teachers won’t let in if you wear sunglasses.11. I’ll do it better if the teacher gives me another chance.12. If you don’t go to Lisa’s party, you’ll be sorry.13. If you stay at home, you’ll get bored.14. If I can’t pass the exam, my parents will be very upset.如果我考试通不过，我的父母将会很失望。

If I’m ill, _I_w_i_ll_s_e_e__a_d_o_c_t_o_r___.
If I’m late, _I_w_i_ll_s_a_y__so_r_r_y_____.
Look and say
If I’m hungry,
I will_e_a_t_s_o_m_e__fo_o_d___.
If I’m tired,
2.You may __p_a_s_s_ (pass) the exam if you _s_tu_dy (study) hard. 3. If you want to record, __p_r_e_ss___(press)
the red light.
用括号内所给词的正确形式填空
1.If the rain __s_to_p__s_(stop) tonight, we will go to the cinema. 2.I’ll buy a computer if I _h_a_v_e__(have) enough money.
Please call me if he comes next Sunday.
If 引导的条件状语从句的基本用法:
主句 一般将来时
祈使句 含情态动词
从句 一般现在时 一般现在时 一般现在时
练一练：
1。如果她早点儿起床，就有时间在家里吃早餐
If she_g_e_ts_ _u_p__a little earlier, she’ll have time to
her.
5.I want to know if he __c_o_m__e_s__(come) tomorrow, if he _w_i_l_l _c_o_m__e__(come), I _w__il_l_g_i_v_e__(give) the massage to

词：
1、every系列
• day
• year
２、频率副词 • month
３、次数 asel•wldeaovymse,r,uyhsaur一 三dall次 次lyy,etohvorfenetcree,en•nti,emw两sveeoes次ermktewtiicme es, 一周两次 tw• imceoarnwineegk
• 如果你站在雨里，就会淋湿。
• 4.If you drop a glass, it breaks. • 如果你把玻璃杯掉在地上，它就会碎。
• 由例句我们可以知道：
• 如果if引导的条件句谈论的是一种 _真__理_/_客_观__事_实___ 时，主句谓语动词直 接用_一_般__现_在__时的动词形式。
每周四次 fo•uarfttiemrensooa nweek 每周六 on S• aetvurednaiynsg
一般现在时的构成
一、系动词be的一般现在时 am, is, are 二、情态动词的一般现在时
情态动词 + 动词原形
三、实义（行为）动词的一 般现在时
主语 + 行为动词 + 其他
• 构成
3. Please tell her my telephone number
if she _w_a_n_t_s (want) to know.
(C) 4. If it ______ sunny tomorrow, I ____
boating.
A. is go
B. will be, go
C. is, will go D. will be, will go
2、以辅音字母加y结尾的动词， 要先将y变为i，再加es
3、以“s, x, ch, sh”结尾的，在 词尾加“es”，发音为[iz]

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。
3. 如果主句是祈使句，从句同样要用一般现在时。
Don’t go and play football if you don’t finish your homework.
10.He _w__il_l _w_a_t_c_h(watch) TV ,if he ___ihe g_o_e_s__(go) to the party, he_w__ill_h_a_v_e_ (have) a great time.
2.If the rain __st_o_p_s_(stop) tonight, we will go to the cinema.
状语从句
在复合句中表示的状语
可以用来修饰谓语（包括非谓语 动词）、定语、状语或整个句子。
状语从句 分类
1时间状语从句
6让步状语从句
2地点状语从句
7比较状语从句
3原因状语从句
8方式状语从句
4条件状语从句
9结果状语从句
5目的状语从句
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
4。如果你经常听英文歌，你将会喜欢英语

八年级第10单元if 引导的条件状语从句1. if 意为“如果”，引导条件状语从句时，既可放在主句前面，也可放在主句后面。

若if条件句放在句首，从句后面通常要加逗号与主句隔开。

例如：If you go there, I'll go too.如果你去那儿，我也会去。

My mother will take me to the park if she is free.如果我妈妈有空，她就会带我去公园。

2. 时态运用：在含有if 引导的条件状语从句的主从复合句中，主句为一般将来时，条件状语从句通常用一般现在时，即遵循“主将从现”的原则。

例如：If he comes, he will bring his violin.如果他来，他就会把他的小提琴带来。

在含有if 引导的条件状语从句的主从复合句中，主句是含有情态动词may/have to/can/must/should等的句子，条件状语从句通常用一般现在时，即遵循“主情从现”的原则。

例如：If you want to lose weight, you must eat less bread.如果你想减肥，必须少吃面包。

You can get good grades if you study hard.如果你努力学习，你可以取得好成绩。

If you drive too fast, you may have an accident.如果你超速驾驶，就可能会出交通事故。

1. if 意为“如果”，引导条件状语从句时，既可放在主句前面，也可放在主句后面。

若if条件句放在句首，从句后面要加逗号与主句隔开。

If you go there, I'll go, too.如果你去那儿，我也会去。

My mother will take me to the park if she is free.如果我妈妈有空，她就会带我去公园。

2. 时态运用：在含有if 引导的条件状语从句的主从复合句中，主句为下列情形之一的，条件状语从句通常用一般现在时。

if引导的条件状语从句教学Teaching aims:Understand and know how to use the conditional clause.Teaching aids: pictures, computer, and little blackboard.Teaching procedures:Step 1 warming up:1.Play a song called“If you are happy, clap your ha nds.” And then the teacher sings the songwith the students together.2.Talk freely:There is a cat called Dudu.It is cute but lovely. It is unhappy, too. I think it may have some problems. Do you know the problems? If you are its owner, what will you do?3.Collect information:Write some sentences about “if” on the blackboard.①If you copy homework, you will start a bad habit.②She will be happy if she joins the party.③I will ask the teacher for help if I don’t understand.④If it’s fine tomorrow, we can go out.⑤Please call me if he is at home.⑥If you don’t hurry up, we will be late.⑦If you study hard, you will pass the exam.Step 2 Discuss and summarize:学生得出结论：①if意为“如果”，这种句子用来谈论事物的影响或者是后果。

25
What are your problems?
What should you do to
say no to your bad habits and embrace（拥抱） 2019 with
a new look?
你应该做些什么来向坏习惯告别，以一个 全新的面貌去拥抱2019？
26
Write a letter to Mr. Yu.
One
Three
20
21
22
23
（三）Your new year resolutions
Mr. Yu wants to make our class better and better,but now I have many problems:
24
1.Some students are always late for class; 2.Some students can't finish the homework in
If I feel happy,If you feel I will sing. happy,
you will sing. If I am happy, If you are happy, I will dance. you will dance.
7
2.引导词：if、unless if…not=unless
time; 3.Some students don't listen carefully in class; 4.Some students aren't friendly to teachers
and classmates; 5.Some students aren't quiet; 6.Some students aren't good at math; …………

It will be sunny tomorrow. We will go to the amusement park. If it is sunny tomorrow, we will go to the amusement park.
Grammar Focus: if 条件句
I have to stay at home.
都表示对事情的结果进行预测。
Can you tell the conjunction (连词) that connects the two parts of the sentences? What does it mean?
What tenses do the sentences use?
一般现在时
_is___ (be) red.
3. Please call me if you come back. if 条件状语从句中，主句是祈使句，从句用 一般现在时表示将来。主祈从现原则。
e.g. Don’ t wait for me if Ia_m____ (be) late.
1. Put up your hands if you _h_a_v_e_ (have) any questions. 2. If it __i_s_ (be) cold tomorrow, I will wear my sweater. 3. He can go home if he_fi_n_is_h_e_s_(finish)his homework.
if 条件句
I have to stay at home. I will be bored. If I stay at home, I will be bored.

I want to go out. You will be wet.

If it is hot, I will go to swim.
If I go to the zoo, I will see the animal show.
If you go to the party, you will have a great time.
If he has free time, he will go for a trip with his students.
I. Fill in the blanks with the correct words
用正确的词形填空
1. I will watch TV every day. My mother will be angry. watch If I ________TV this weekend, will _____angry. be my mother _____ 2. He will have a strange haircut. The teachers won’t agree. If he _____ has a strange haircut, won’t _______. agree the teachers______
用括号内所给动词的适当形式填空。 forget (forget) your tickets, you 1. If you ______ go can’t ____(go) to the concert. fails (fail) the test again, the 2. If Jenny _____ will ask (ask) her mother to teacher _______ come to school. play (play) music too loud, your 3. If you _____ will be roommates ________(be) mad at you. to drink 4. Andy, would you like something _______ (drink)? shout (shout) at 5. Boys and girls, don’t _____ Individual the party. activity

--I’ll stay at home and watch TV.ຫໍສະໝຸດ A. rainB. rains
C. will rain
D. is raining
(C) 6. If he ______, I ______ him the time.
A. comes, tell B. will come, will tell
won’t
2. 如果主句含有must /c主an情/m从a现y 等情态
动词，从句一般用_一__般__现__在__时__。
You must stop if the traffic light __i_s_ (be) red.
3. 如果主句是祈使句， 从句也常用
_一__般__现__在__时__。
主祈从现
If I go to London, I will see the Big Ben.
If I go to London …
I will see the Big Ben.
If I go to Buckingham Palace,
I can take a photo of the Royal Guard.
If I oversleep …
I miss the bus.
If I miss the bus, I am late for school.
If I am late for school, my teacher gets angry.
If clause
Main clause
• If + Present tense will / can / may / must + verb
中考预热
C 1. You can surf the Internet ______you want to know about the 2020 World Middle School Games. A . Until B . After C . if D . Unless

if条件状语从句---用法
（2 ） If it stops snowing, we can go out. If you love your parents, you should help them do the housework. If you want to lose weight, you must eat less junk food.

A. can pass, will work C. passes, will work 答案：D
B. will pass, will work D. can pass, works
翻译：如果明天天晴，他可能会去看望他的叔叔。
If it is sunny tomorrow, he may visit his uncle.
英语 人教版 八（上）
Unit 10 If 条件状语从句
if条件状语从句---概念
连词 if 意为“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。
if条件状语从句---结构

结构： if+ 陈述句，主语 + 谓语（或者主语 + 谓语 +if+ 陈述句），意为“如果... 就...”。 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。
从句可以放在主句前，用逗号与主句隔开； 从句也可直接置于主句后。 If I get up at 9:00, I will be late.


如果我早上九点起床，我将会迟到。
I will be late if I get up at 9:00.