Uni10 if 引导条件状语从句 课件 人教版英语八年级上册

4.Hurry up if you _d_o_n_’t__w_a_n_t(not want) to be late.
Look and say
you
get up late
If you get up late, you’ll be late for school.
late for school
I我
If I have a lot of money, I will buy a big house.
Translation:
如果我有足够的钱，我就去环游世界。
If I have enough money, I will travel around the world.
=I will travel around the world if I have enough money.
Read and summarize 读下列例句，总结if的用法
If you study hard, you’ll pass the exam. =Study hard, and you’ll pass the exam.
If you don’t hurry up, you’ll be late. = Hurry up, or you will be late.
Please call me if he comes next Sunday.
用法三：主句是祈使句，从句 也要用一般现在时。 （主祈从现）
Exercises： 1.I _w_il_l _s_t_a_y_(stay ）at home if Lucy _co_m__e_s （come） tomorrow.
If you want to lose weight, you must eat less bread.
You must stop if the traffic light is red.
用法二：主句含有must, may, can等情态 动词，从句也要用一般现在时。
（主情从现）
Don't go and play football if you don't finish your homework.
1、unless 除非，如果不...
Unless he invites me， I won’ t go to his party. = If he doesn’t invite me, I won’t go to his party.
2、as (so) long as... “只要...就...”
You will get good grades as long as you study hard.
(B )1. He will help me with my math if he ____ free.
A. was B. will be C. would D. is
(C ) 2. Please tell her my telephone number if she____
to know.
A. want B. wants C. will want D. wanted
A. is; go
B. will be; go
C. is; will go D. will be; will go
(B ) 5. ____ you don’t hurry up, you’ll miss the early bus.
A. If B. Unless C. Although D. Until
If it is fine tomorrow, we will go to the park.
I will go to the library if I finish my homework before ten o'clock.
用法一：主句是一般将来时， 从句用一般现在时。 （主将从现）
If you finish your homework, you can go home.
同义句转换 2、借助介词with或without来转换。 If you help me，I will finish my work soon. = With your help，I will finish my work soon.
If there is no water, fish will die. =Without water, fish will die.
Summary:
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，主将从现不一般； if还有"是否"意，宾语从句放后边。
If you study harder， you will succeed, try your best to study harder.
Hale Waihona Puke Homework:If的两面性(两个意思)
1、if : “如果”, 引导条件状语从句
I will go to the cinema if I am free
tomorrow.
主将从现
2、if: “是否”,引导宾语从句
I don't know if he will come tomorrow. 从句可用将来时
Practice
Position (位置）
If it rains tomorrow, I will stay at home.
if clause
main clause
I will stay at home if it rains tomorrow.
main clause
if clause
从句在主句前时,__用__(用/不用)逗号隔开； 当主句在前时，则_不__用__(用/不用)逗号。
英语人教版八年级上册Unit 10
If 引导条件状语从句
什么是条件状语从句？
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引导的条件状语从句表示假如有从句 的动作发生，就会有主句动作的发生。)
If she is hard-working, she will get good grades.
we
If it is sunny this Sunday, we will go fishing.
ill
I我
see a doctor
If I'm ill , I will see a doctor
(C ) 3. I don’t know if my uncle____. If he ____, I will
be very happy.
A. comes; will come B. will come ; will come
C. comes; comes
D. will come ; comes
( D) 4. If it ___sunny tomorrow, I _____ boating.
2. If he_d_o_e_s_n_’t__c_o_m_e_ (not come), I _w_o_n_’t__g_o_ (not go) swimming alone.
3.If we _s_ta_r_t__(start) now, we can _fin_i_s_h_ (finish) the work on time.
Attention 注意事项
在if引导的条件状语从句中,当主句是 一般将来时时，要用will＋v，不能 用be going to 结构。
eg: I will help you with your English if I am free tomorrow.
同义句转换
1、借助“祈使句＋and/or＋简单句”句型来转换。 其中and表示顺承关系，or表示转折关系。
Tell a story with “if”:
If I play computer games, I will get bad grade.
If I get bad grade, my parent will be angry with me.
If my parent is angry with me, I will be sad.
如果
1. Betty will visit the History Museum if it _d_o_e_sn_’_t_r_a_in(not rain) tomorrow.
2.Ben wants to know if it _w_il_l _b_e__(be) fine tomorrow.
是否
除了if 之外，是否还有其他连词 可以引导条件状语从句