第三部分

語法專題精講練專題一

動詞知識必備

動詞的分類命題點1情態(tài)動詞

在形式上，情態(tài)動詞一般沒有人稱和數(shù)的變化。其本身詞義不完全，不能單獨使用，必須與動詞原形一起構(gòu)成謂語。其否定式一般是在其后加not，一般疑問句通常將其提到句首。1.情態(tài)動詞的基本用法情態(tài)動詞用法例句can表示能力，意為“能,會”。其否定式為can’t，過去式為could。Jim

can

sing

songs.表示請求、允許，意為“可以”。Can

I

play

basketball

now？情態(tài)動詞用法例句couldcan的過去式，意為“能，會”，表示過去的能力。其否定式為couldn’t。Lily

could

swim

at

the

age

of

5.在疑問句中表示委婉地請求?！咀⒁狻炕卮鹨詂ould引出的一般疑問句時，用can，不用could?！狢ould

you

please

lend

me

your

phone？—Yes,

I

can./Sorry,

I

can’t.續(xù)表情態(tài)動詞用法例句must表示主觀看法，意為“必須，一定”?！咀⒁狻坑蒻ust引出的一般疑問句，肯定回答用must；否定回答用needn’t/don’t

have

to,不能用mustn’t。I

must

work

hard.續(xù)表情態(tài)動詞用法例句mustn’t意為“一定不要，禁止”。You

mustn’t

talk

in

the

library.have

to意為“不得不”，多表示客觀必要。I

have

to

get

up

early

tomorrow.續(xù)表情態(tài)動詞用法例句need意為“需要”，常用于否定句和疑問句中,其否定式needn’t意為“不必”。【注意】回答以need引出的一般疑問句時，肯定回答用must/have

to，否定回答用needn’t?！狽eed

I

do

the

work

at

once？—Yes,

you

must（have

to）./No,

you

needn’t.Alex

needn’t

attend

the

meeting.續(xù)表情態(tài)動詞用法例句may表示請求、許可，意為“可以”?！咀⒁狻坑蒻ay引出的一般疑問句，其否定回答用can’t/mustn’t，不用may

not。—May

I

sit

here？—Yes,

you

may（can）./No,

you

can’t

（mustn’t）.mightmay的過去式。表示請求、許可，語氣比

may

更委婉。Might

I

ask

you

a

question？續(xù)表情態(tài)動詞用法例句should意為“應(yīng)該”，表示要求和命令，也可表示勸告或建議。其否定式為shouldn’t。You

should

come

to

school

on

time.表示征詢意見，常用于疑問句中。Should

I

leave

at

7:00

p.m.?續(xù)表情態(tài)動詞用法例句had

better意為“最好”，沒有人稱和數(shù)的變化，否定式為had

better

not。You’d

better

come

back

early

today.shall常用于疑問句，多用于第一、三人稱，表示請求或征求意見，意為“……好嗎？”Shall

we

go

to

the

zoo?will表示意愿或請求，用于疑問句中，常用于第二人稱。Will

you

please

pass

the

book

to

me?would表示詢問或請求，語氣比will更委婉。Would

you

please

help

me

with

my

maths?續(xù)表2.情態(tài)動詞表推測的用法情態(tài)動詞用法例句must表示非常有把握的肯定推測，意為“一定，肯定”。It

must

be

raining

outside.

My

father’s

clothes

are

so

wet.may表示把握不大的肯定推測，意為“有可能，也許”。John

may

come

back

at

5:00

p.m.could/might表示沒有把握的肯定推測，意為“有可能，也許”，可能性低于may。

might表示可能性最低。The

pencil

might/could

be

Bob’s.情態(tài)動詞用法例句can’t表示十分有把握的否定推測，意為“一定不，不可能”。He

can’t

be

having

a

meeting.

I

saw

him

just

now.may

not表示把握不大的否定推測，意為“可能不”。Mandy

may

not

come

tonight.續(xù)表隨堂練一、用方框中所給單詞完成句子must

should

shall

can’t

have

to

needn’t1.______

we

invite

Jim

to

dinner?

It

has

been

a

long

time

since

we

got

together.Shall2.The

lady

beside

the

window

______

be

my

neighbor.

She

is

on

her

business

trip.can’t3.The

result

of

this

English

exam

______

be

great

because

everyone

did

a

good

job

these

days.must4.There

will

be

no

hot

water

in

an

hour.

We________

take

a

quick

shower.have

to5.You

________

answer

my

questions

right

away.

Just

think

them

carefully.needn’t6.Parents

_______

put

the

dangerous

things

like

knives

and

medicine

away

in

the

house

to

keep

children

safe.should二、句子盲填1.You

________

take

photos

here!

Look

at

the

sign.

It

says

“No

photos”.mustn’t2.Nowadays,

some

robots

are

very

human-like.

They

_____

walk

and

dance.can3.All

around

the

world

many

wild

animals

are

in

danger.

We

________________

lose

them

all

one

day.may/might/could4.—May

I

play

basketball

outside

now,

Mum?—No,

you

_____________.

You

must

clean

your

room

first.can’t/m