if引导的条件状语从句和宾语从句

if引导的条件状语从句和宾语从句if引导的条件状语从句和宾语从句13/13PAGE13if引导的条件状语从句和宾语从句if引导的条件状语从句和宾语从句If的用法if的条件从句分为真实0_v6v6zkg6"条件从句和虚拟条件从句。真实条件从句：真实条件从句适用于%8E%B0&hl_tag=textlink&tn=SE_hldp01350_v6v6zkg6"主将从现，是假设有可能发生的。位置在if

引导的条件状语从句中，既可以放在主句之前，也可以放在主句之后。若if

条件句放句首，从句后面要加逗号，和主句隔开。Youwillcatchthebusifyougetupearly.=Ifyougetupearly,youwillcatchthebus.时态1.（主祈从现）主句：一般现在时态（包含祈使句和含有情态动词can,may,must等的句子）从句：一般现在时态2.（主将从现）主句：一般将来时态从句：一般现在时态3.从句:现在进行时，主句:一般将来时

If

you

are

looking

for

Peter

you’ll

find

him

upstairs.

如果你是在找彼得，上楼就会找到他。

4．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.

如果你吃完了，我就叫服务生来算账5.if

条件句谈论的是重复发生和预示要发生的情景和事件，则主从句大多用一般现在时态。如：If

bears

are

in

danger

,they

attack

people.

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态时，不能使用begoingto结构，而要用will.在if引导的条件状语从句中,不能使用some,而要用any.同义句转化借助于祈使句+and∕or+简单句转化，and表示顺承，or表示转折。例如：(1)Ifyouworkhard,you’ll

passtheexam.Workhard,andyou’llpasstheexam.(2)Ifyoudon’thurryup,you’llbelate.Hurryup,oryou’llbelate.借助于介词with或者without来转换例如：Ifyouhelpme,I’llfinishmyjobsoon.Withyourhelp,I’llfinishmyjobsoon.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，主句多用将来时；条件句表事实，主句常用现在时。虚拟条件从句:虚拟条件从句是假设不太可能发生的。

IF的HYPERL虚拟语气有三种：

内容从句主句

与现在事实相反动词过去式（be用were）would/could/should/might+动原

与将来事实相反should/wereto+动原would/could/should/might+动原与过去事实相反had+过分would/could/should/might+have+过分

下面三句依次是上面三种情况的例句：

IfIwereyou,Iwould/could/should/mightdothat.

IfIhadknowthatxtlink&tn=SE_hldp01350_v6v6zkg6"yesterday,Iwould/could/should/mighthavetoldyou.

Ifitshouldrain,thecropswould/could/mightbesaved.

If引导的宾语从句一．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。【例句】Iwanttoknowifhelivesthere.我想知道他是否住在那儿。HeaskedmeifIcouldhelphim.他问我是否能帮他。【考查点】if、whether引导的宾语从句的区别1.if或whether引导宾语从句时，作“是否”讲，常放在动词ask、see、say、know和findout等后面。一般情况下，两者常可换用，在口语中多用if。【例句】Nobodyknowswhether/ifitwillraintomorrow.没有人知道明天是否下雨。Lucyaskedwhether/iftheyhadacottonsweater.露西问他们是否有棉制的毛衣。二.注意事项：if或whether引导宾语从句时，要注意三个方面，即连词、语序和时态。1.if或whether既不能和that或其他连词（副词）同时使用，也不能省略。【例句】我不知道他今天是否会来。[误]Idon’tknowthatif(whether)hewillcomeheretoday.[正]Idon’tknowif(whether)hewillcomeheretoday.他走过来看看猫是否出了毛病。[误]Hecametoseewhatif(whether)therewasanythingwrongwithhiscat.[正]Hecametoseeif(whether)therewasanythingwrongwithhiscat.2.if或whether引导宾语从句时，虽具有疑问的意义，但其从句应用陈述句的语序。【例句】Didyouknowthewaytothehospital?Theoldwomanaskedme.Theoldwomanaskedmeif/whetherIknewthewaytothehospital.老妇人问我是否知道去医院的路。if或whether引导的宾语从句应和主句的时态保持一致。即主句为一般现在时，从句用任一种时态；主句为一般过去时，从句则用过去时中的任一种时态。【例句】Idon’tknowif(whether)hehascomehere.我不知道他是否来过这儿。Tomaskedif(whether)Ihadreadthebook.汤姆问我是否看过这本书。三．If和whether两者不能互换的情况1.只能用whether的情况在动词不定式之前只能用whether：【例句】Ican’tdecidewhethertostay.我不能决定是否留下。2.在whether…ornot的固定搭配中：【例句】Iwanttoknowwhetherit’sgoodnewsornot.我想知道它是不是好消息。3.在介词后，只能用whether：【例句】Hisfatherisworriedaboutwhetherheloseshiswork.他的父亲担心他是否会失去工作。4.用if会引起歧义时：【例句】Couldyoutellmeifyouknowtheanswer?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。【考题链接】Idon’tknow_________theycouldpasstheexamornot.A.whyB.ifC.thatD.whether答案：D解题思路：本题考查if与whether的区别，在whether…ornot的固定搭配中通常只用whether。练习题：句型转换1.Dotheywantfriedchicken?Heaskedtheboys.(改为宾语从句)Heaskedtheboys_______they______friedchicken.2.WasthewatchmadeinShanghai?Idon’tknow.(改为宾语从句)Idon’tknow_______thewatch_______madeinShanghai.3.“Doyouwanttotrysomethingnew?”Tom’smotheraskedhim.(同义句转换)Tom’smotheraskedhim_____________________totrysomethingnew.答案：1.if/whether,wanted2.if/whether,was3.if/whetherhewanted一、用所给词的适当形式填空

1.If

you

________(feel)

tired,

you

_______________

(have)

to

have

a

rest.

3.

If

there

__________(be)

fewer

trees,

there

_______________(

be)

more

pollution.

5.

If

Marcia

_____________(live)

alone,

she

___________________(

keep)

a

pet

parrot.

6.

Lana

________________(

buy)

a

new

dress

if

the

old

one

____________(be)

out

of

style.

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.

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

Peking

University.

16.

如果努力学习，你就会取得好成绩。

If

you__________

_________,

you

___________

good

_____________.

17.

他如果看电视太久了，他的父母会不高兴。

If

he

_________

TV

too

much,

his

parents

__________

__________

unhappy.

18.

如果我们为他组织生日聚会，大家都会来的。

Everyone

________________

if

we

_____________

a

birthday

party

__________

him.

19.

如果明天不下雨，我会和你一起去公园的。

If

it

__________

__________

tomorrow,

I

______________

go

to

the

park

_________

you.

21.

如果他有空，他会帮助你的。

If

he

_________________,

he

_________________

you.

23.

你如果抄同学的作业就不能学好各门功课。

You

_______

_____

good

at

all

the

subjects

if

you

______

the

other

students’

homework.

Ⅰ单项选择（1.If

you

_____

to

the

party,

you’ll

have

a

great

time.

A.

will

go

B.

went

C.

go

D.

going

2.

It

will

be

a

long

time

____

Peter

_____

his

work.

A.

since,

has

finished

B.

after,

finishes

C.

when,

will

finish

D.

before,

finishes.

3.

What

will

father

_____

us

from

Japan?

A.

take

B.

bring

C.

carry

D.

make

4.

Weifang

is

famous

______

kites.A.

for

B.

to

C.

on

D.

with

5．I

____

her

the

answer

if

she

____me.

A.

can

tell,

will

ask

B.

will

tell,

will

ask

C.

would

tell,

ask

D.

will

tell,

asks

6.

–

What

are

you

going

to

do

tomorrow?

--We’ll

go

to

the

library

tomorrow

if

it

___.

A.

isn’t

rainB.

rain

C.

won’t

rainD.

doesn’t

rain

7.—Do

you

know

when

he

will

come

back

tomorrow?

--Sorry,

I

don’t

know.

When

he

____

back,

I’ll

tell

you.

A.

comes

B.

will

come

C.

come

D.

may

come

8.

What

will

you

do

if

you

_____

to

the

old

folk’s

home

visit?

A.

go

B.

went

C.going

D.

will

go

9.

If

I

eat

____

food,

I’ll

be

very

fat.

A.

too

many

B.

many

too

C.

too

much

D.

much

too

10.

I’ll

give

the

book

to

him

if

he

___

her