主将从现讲解+习题

主将从现

主将从现：是指在时间状语从句和条件状语从句中，主句是一般将来时，从句用一般现在时（标志词）

if

as long as

unless

when+从句，

主句.

while （一般现在时）（一般将来时）

as soon as

until

before

——引导条件状语从句的词（if、as long as、unless）

If you ask him, he will help you.

As long as you ask him, he will help you.

I’ll go there tomorrow unless it rains.

——引导时间状语从句的词

when , while , before , after , until , till , since , as soon as ,

——1.主将从现

主句是一般将来时，从句用一般现在时。

When I grow up, I’ll be a doctor. If he goes to the party, you will be happy.

——2.主祈从现

主句是祈使句，从句用一般现在时。Don’t laugh at me when I make a mistake.

Put it in your diary before you forget. 用记事本记下免得忘了。

——3.主情从现

主句中含有情态动词，从句用一般现在时。

You should be quiet when you are in the reading room.

A baby deer can stand as soon as it’s born. 小鹿一生下来就能站着。

You can get a better job if you speak a foreign language.

要是你会说一种外语，那你就会找到更好的工作。

通常出现情况

1. “主将从现”用于时间状语从句

As soon as I get through with my work I’ll join you. 我工作一做完就来找你们。

Before they drive any of the buses, they will have to pass a special test.

然而在驾驶公共汽车前,他们必须通过专门测验。

My mother will be very angry with me when she finds out where I’ve been.

我母亲要是知道我到过那地方一定会大怒。

We’ll pay you half up front and the other half when you’ve finished the job.

我们先付给你一半钱，剩下的一半等你干完了再付。

2. “主将从现”用于条件状语从句

If (it is) necessary I will come at 6. 如有必要，我6点钟来。

If today is Wednesday, the day after tomorrow will be Friday.

今天要是星期三，后天就是星期五。

If you train hard, you’ll make a good footballer. 你要刻苦训练就能成为优秀的足球运动员。If past experience is anything to go by, the plane will be late.

过去的经验要是还靠得住的话，这飞机会晚点的

3. “主将从现”用于让步状语从句

We’ll go even if it rains. 即使下雨我们也去。

He’ll come even if he’s ill. 他即使生病也会来。

Even if he had the money, he wouldn’t buy it. 他即使有钱也不会买它。

He’ll probably say no, though it’s worth trying. 他很可能不同意，但不妨去试探一下

【Exercise 】练习

1. If I come, I ________ ( see ) you.

2. If it is fine, we______( go ) for a walk.

3. If it rains, they _________ ( stay ) at home.

4. You will spoil it if you ______ ( not be ) careful.

5. We will be very much pleased if you _____( come ).

6. Will you help me if I _____ ( need ) you.

7. They will get wet if it ____ ( rain ).

8. We will answer if we ___( can ).

9. If you eat too much, you ______( get ) ill.

( ) 10. ---What will Bill do if he ____in the test?---He will try again.

A. fail

B. fails . will fail D. is failing

( ) 11. Please tell her the news when she_____. OK, I will.

A. comes

B. will come.

C. come

D. would come

( ) 12. The students will plant trees if it ___ tomorrow.

A. didn’t rain

B. has n’t rained

C. won’t rain

D. doesn’t rain

( ) 13. We__ home if there is no bus. ---Oh, what a pity!

A. will walk

B. have walked

C. walked

D. walk ( )

14 .If it _____ tomorrow, I’ll go by car.

A. rain

B. will rain

C. rains

D. would rain ( )

15.If Mary____next Sunday, we will go boating together.

A. will come

B. comes

C. shall come

D. should come ( )

16. --- Don’t forget to ask him to write to me.

--- I won’t. As soon as he____, I’ll ask him to write to you.

A. will come

B. came

C. comes

D. is coming

( )17. --- Can I go to Beijing for my holiday, Dad?

--- You can when you _______ a bit older.

A. will get

B. get

C. are getting

D. got

( )18. If he _______ harder, he will catch up with us soon.

A. study

B. studies

C. will study

D. studied

( )19. Frank ____to see his grandma if he __ free tomorrow.

A. will come; will be

B. comes; is

C. will come; is

D. comes; will be