第八次课 情态动词

情态动词：情为何物之情态动词~

1，推测（对现在，未来的推测）

练习案例：

It ——be my mother. because someone is knocking at the door, and mom always go back home at this time（mom is not at home）

2，It——be my mother（mom is at home），someone is knocking at the door

黄金规律：can 无肯定may无疑问；Must只能用于肯定句，不能用于否定疑问句；

could全部都可以；must 70%；can/could；may/might 40%；may not/might not可能不20%；can’t/ could not 0%

需要注意的是might不是may的过去式，同理：could也不是can 的过去式

练习：

1，the cake is very sweet, you ——put a lot of sugar.

2，It——be very expensive, I never dream of buying it

3，It ——be correct.(做单选题并不完全确定这个前提)

4，She looks very happy，she——have passed the examination. A, should B，could C，must D might

5，Helen——go on the trip with us, but she isn’t very quiet sure A, should B，may C，must D can

3，定义：四个基本定义

1，Can：I can swim（表示能力）；

2，Can the man be his father(表示可能)could是它的同义词；

3，Can I come in？（表示允许），could是can的委婉语气.

Could I come in？不认识的人表礼貌

4，May：表示可能（might，can，could）；表示允许的语气（may，might）

Can I come in? could I come in? may I come in? might I come in? (越来越委婉) 回答全部用can回答

Must: it must be his mother(表示一定)；

must you leave now？（表示必须，与have to同义词）

4，Need:（表示需要，必要）做实意动词和情态动词

练习：他明天需要来(情态动词相当于can)

He need come tomorrow

He needn’t come tomorrow

Need he come tomorrow?

他明天需要来（实意动词相当于want）

He needs to come tomorrow.

He doesn’t need to come tomorrow

Does he need to come tomorrow?

1，Could you tell me? —————

A, where she lives? B, where she lived?

2，Could I know your name? yes you ————

A，could B，can

3，if you are not careful in the street, a car——hit you

A, can B, may C, should D, must

4，问答

Must与can’t的区别：

Must不能用于否定和疑问，但是can’t 可以，所以是它的替身You have been travelling all day. You——be very tired

The restaurant——be very good. It’s always full of people

That restaurant——be very good. It always empty.

Must 与have to的区别

现在时中，must表示主观，have to 表示客观，不得不

I ——get up early at 6 o’clock tomorrow morning

In china many children—— wear uniform when they go to school. She is really nice person. You —— meet her.

He ——have English online course on every Saturday evening.

过去时中，只用had to

Last night Tom became ill, we——call him today.

四大词的肯定否定句中的回答：

Can: can/can’t

May：can/ can’t,

Must: must/ needn’t

Need: must/ needn’t

练习：

May I watch tv for a while?

No, you ——. You have to finish your homework first! A, shouldn’t B, needn’t C, mustn’t D, won’t