Model Verbs

Model verbs + V1

Model verbs: can, could, may, might, will, would, shall, should, must.

Ability & Possibility

** general ability or possibility in the present can or be able to.

I can speak English.

I am able to work 24 hours non-stop.

I can’t drive a car.

She wasn’t able to drive a car.

** talk about the ability to do something on a single occasion in the past was/were able to, not could.

I was able to explain the problem to her.

I could (future possibility) explain the problem to him. (Wrong)

** talk about the ability to do sth in the future, will be able to, can.

I will be able to make a lot of money in the future. / I can make a lot of money in the future.

** will be able to, not can, to talk about an ability we will have, or skill will acquire in the future.

I will be able to drive a car by next summer so we can hire a car. (Now I can’t drive.)

** can/could, to talk about typical behavior or events.

It can rain a lot at this time of the year.

He could be cool when he wants to be.

** could + have + V3: to talk about an unfulfilled possibility in the past.

He could have gone to New York for the winter holiday, but he decided not to go there.

I could have stayed in the Netherlands if I wanted to.

** verbs succeed and manage suggest that something is achieved with difficulty.

Did you succeed in passing the exam? / Have you managed to get a visa to Russia?

** be able to: Not can. Can mix with other grammar.

I like being able to work from home. / We have been able to work long hours.

Degrees of Certainty

** to show how certain we are that something is true or will happen in the present or future. May, might, could, must, can, can’t.

** May (may not), might (might not), could, (NOT couldn’t): to talk about something we think possible now or in the future.  

He may/might/could take a trip to London next summer.

He is not in his office, but he may/might/could be working from home.

** We don’t use “Can” for future possibilities.

There can be snow this evening. (wrong)

There may/might/could be snow this evening.

** we use must or have to when we are certain something is true in the present.

He must be on his way home because he doesn’t pick up my phone.

You have to be joking!

** we use “can’t” we are certain that sth is impossible. 

You can’t be full. / You can’t be hungry. / You can’t be angry about this.

** Theory, talk about which is possible in theory, can, or could.

There can/could be life on Mars. I think you could go by train.

** Model perfect: speculation about the past.

may/might/could/can’t/couldn’t have + V3

may/might/could/can’t/couldn’t have been Ving.

** talk about the possibility that something happened, we use

Could/may(not)/might(not) +have + v3

May/might/could/ have been + Ving.

He might not have treated 200 patients in an hour.

He could/might/may have been sleeping because he didn’t answer the phone.

** when we are certain about sth happened, must have + V3, or must have been + Ving.

You are wet, it must have been raining outside.

** when we are certain something didn’t happen. can't/couldn’t have +V3 or can’t/couldn’t have been Ving:  He couldn’t have killed the patient because he was with me.

Obligation and Necessity

** to say that it is important to do or not to do something: must/mustn’t, have (got)to.

**Must/ mustn’t:

**When the speaker feels that an action is necessary.

You mustn’t be late for work.

** by someone in authority. e.g., parent or teacher, boss.

You must hand in your homework by Friday.

You mustn’t talk to your father like that.

** in written rules, instructions, and notices.

All patients must make an appointment to see the doctor.

** have (got) to when an action is necessary because someone else requires it or because of a rule or law.

You have to be at the hospital at four.

You have to get a visa before any international travel.

** We don’t use “must” in questions. Use “have to”, will have to, had to

Must you arrive at four? (Wrong)

Do you have to arrive at four? / Do you have to follow me?

You will have to book a flight ticket before traveling.

As a student, I had to pass all the exams to get my degree.

** need to (necessity), needn’t, don’t need to , didn’t need to, needn’t have + V3. – lack of necessity.

You need to eat more in order to get well soon.

You don’t need to come if you are busy.

Do I need to bring anything with me?

Advice, recommendation, and criticism

** we use should/shouldn’t or ought (not) to, to give advice for the present and future.

You should lose some weight.

You shouldn’t stay up late at night.

You ought to be leaving soon.

You ought to ask for permission.

** we use should and ought to with: I think and do/don’t you think…?

Do you think I should learn Spanish?

Do you think I ought to move to Germany?

Don’t you think I should marry her?

** strong advice or make a recommendation for the present and future. Must and mustn’t.

You must come over for a meal.

We must meet before I fly to London.

You must work hard if you want to make more money.

** had better (not) + v1: give advice or a warning.

You had better arrive on time for the interview.

You had better not tell her about it. [tell, told, told]

You had better learn foreign languages if you want to move to Europe.

** should/shouldn’t or ought to, have + V3 or should/shouldn’t or ought to have been ving: criticize sb/sth happened in the past.

You should have told her about this issue. (You didn’t talk to her).

You shouldn’t have broken my heart. (You broke my heart).

You shouldn’t have written this letter to her. (You wrote it).

Permission, requests, offers, and suggestions

Permission:

** to talk about permission or lack of permission in the present or future, we use can’t, am/is/are(not) allowed to,  and may(not).

You can’t (aren’t allowed to) park your car in front of my house.

You may stand or sit, whichever is more comfortable.

** may (not) and must (not) are sometimes used in notices and written rules.

You may not bring meat products into the country.

You mustn't smoke here. / May I come in?

** permission in the past, could/couldn’t, was/were (not) allowed to.

We weren’t allowed to go to school without a uniform.

You were allowed to bring food to the classroom.

** ask for permission, can, could (more polite), may(formal). We can’t use “be allowed to”

Can I borrow your pen?

May I sit here?

Could we wait inside?

Request:

** Can I /you…? could I/you…? (More polite)

Can I have a glass of water?

Could you help me lift the box? (ability)

** will you…? Would you…? (More polite).

Would you phone me later? (desire)

Would you please be slower?

** would you mind + Ing? Or would you mind if I (past simple) (more polite)?

Would you mind opening the window?  Yes, I would (No)/ No, I wouldn’t. (Yes, of course).

Would you mind if I smoked here? Yes, I would.

Would you mind if I opened the window? No, I wouldn’t.

Offers

** shall I/we…? Shall (more polite), should

Shall we start?

Shall we dance?

** would you like…? (polite)

Would you like a cup of coffee?

Would you like to play chess?

**I will/ let me (informal).

Let me make you a sandwich.

I will make you delicious soup.

** can/could I…? or may I…(formal).

Can I help you?

May I take your coat? (Cloaking Room)

** I/we can/could (polite).

I could help you if you like (want).

Suggestions

** shall we…?

Shall we go out for dinner?

Shall we eat pizza?

** we can/could (more polite)

We could see a film if you want.

**why don’t we….?/ let’s (informal).

Why don’t we go to the cinema?

Let’s cook pizza.

** what/how about + Ving (informal)?

What about having dinner at my place next week?

How about going on holiday?