Modal Verbs(Can, may, must)-人教版

发布时间:2016-11-9编辑:互联网

Modal Verbs(Can, may, must)

Rui yi ling

Teaching content:

Modal verbs (can, may, must)

Teaching aims:

1. Review and master the usages of some modal verbs like “can, may, must”.

2. Sum up and grasp the structures of these modal verbs.

Teaching important point:

How to correctly use modal verbs, esp. for the ones expressing possibility.

Teaching difficult points:

How to correctly choose modal verbs in different situations

Teaching type:

A revision lesson

Teaching methods:

Review, explanation, inductive methods.

Teaching aids:

A projector

Teaching procedures:

Step 1 Greetings

Greet the whole class as usual.

Step 2 Revision and Presentation

T: We have learned modal verbs before. Now let’s have a little quiz.

(Show some sentences on the screen.)

1. The light is on. 1) Perhaps he is at home.

2) I’m sure he is at home.

2. The light is off. 1) Perhaps he is not at home.

2) I’m sure he is not at home.

Get Ss to change into another four sentences according to the situations. Ask four students to write their answers on the Bb, and then check the answers with the whole class.

Answers: 1. The light is on. 1) He may / might / could / be at home.

2) He must be at home.

2. The light is off. 1) He may not be at home.

2) He can’t be at home.

Step 3 Explanation

T: Let’s sum up these modal verbs. First get Ss to read through the points on Page 60 in revision book, and then show the following on the screen.

He may be at home. (“Perhaps”)

May He may not be at home. (“Uncertain”)

You may go home. (“Permission”)

(Expressing “guess” in the affirmative or interrogative.)

He can’t be at home. (“Be certain---not”)

It can be warm in winter. (“Occasional possibility”)

Can He can speak English. (“Ability”)

You can leave now. (“be allowed to---” “have a right to---”)

Can you help me? (“Request”)

(Expressing “guess” in the interrogative or negative.)

He must be at home. (“Certain”)

Must I must go home. (“What is necessary”)

You mustn’t smoke here. (“Be forbidden to---”)

(Expressing “guess” only in the affirmative.)

T: Now let’s continue with some synonyms and sentences. Look at them on the screen.

(Give the following on the Screen.)

Can / be able to

1. He can swim.

2. He was able to swim across the river when he was ten.

3. With the help of his friends, he was able to finish the work on time.

T: For “ability + particular action” usually use “be able to”. However, it is relaxed in the negative. You can use either of them. “Be able to” sometimes means “succeed in doing sth.” which can’t be replaced by “can / could”.

Must / have to

1. There is no bus. You have to go home on foot.

2. You must finish your homework before going home.

T: “have to” means “be forced to”. “Must” means “It is necessary or important to do---”

1. --May I watch TV after supper?

--Yes, you may.

--No, please not. / you mustn’t.

2. –Must we do it now ?

--Yes, you must.

--No, you needn’t. / don’t have to.

3. –Need I type this letter again?

-- Yes, you must.

--No, you needn’t.

Step 4 Practice

Rewrite sentences. (Give Ss a few moments. Let them do some relevant exercises on the screen.)

1. Perhaps we will have a good trip.

We_____ have a good trip.

2. I’m sure it isn’t made of gold.

It _____ be made of gold.

3. I’m sure that restaurant is a good one.

That restaurant _____ be a good one.

4. There is much gas here, you ___ smoke here.

Step5 Summary of the usages of modal verbs which express “guess”

T: All right. Look at the form on the screen.

(Show the following on the screen, then begin to explain)

General Continuous Past

Affirmative Must/may/might + v. Must/may/might+be+doing Must/may/might+have+p.p.

Interrogative Can/could + v. Can/could + be+doing Can/could + have +p.p.

Negative Can’t/couldn’t + v. Can’t/couldn’t +be + doing Can’t/ couldn’t + have +p.p.

T: In affirmative sentence, we use “must+V” or “must be doing” to express present or present continuous situation. “Must +have + p.p.”is used to express past situation or the one which has already happened. For example:

Where is Mary? --- She must be in the library.

Now he must be waiting for us at the school gate.

It must have rained last night, for the ground is wet.

It is the same with other modal verbs like “may, can---” But remember “may” is used in the affirmative or negative. “Can” mainly in the negative or interrogative.

Look at the following examples. (Shown on the blackboard.)

He may be at home. Let’s go and see him.

It may/ might have rained last night.

The boy is honest. He can’t tell lies.

Can he have left yesterday?

Step 6 Practice

Fill in the blanks using must/might/may/can/could and their negative forms.

1.-Look! Someone is coming: Who ____ it be?

--It ___ be the headmaster.

--It ___ be him. He has gone to Shanghai.

--It ____ be Mr. Yang. He looks like the headmaster.

2. – Could I borrow your dictionary?

--Yes, of course you ____.

3. I thought you ___ like something to read, so I bought you some books.

4. Peter ___ come with us tonight, but he isn’t very sure yet.

5. She doesn’t answer the bell. She ___ be asleep.

6. The ground is wet. It ____ have rained last night.

7. He is writing with a pencil. He ___ have lost his pen.

8. A computer ___ think for itself; it ___ be told what to do.

(Get Ss to do some exercises on the screen individually, and then discuss them in pairs, at last check their answers with the whole class.)

Homework:

Finish off the exercises.

To continue reviewing Modal verbs.