1. Where do MAVs come from?
MAVs are typical of Germanic Languages – English, German, Dutch, Friesian, ……
English German Dutch
Can Kann Kan
Shall Soll Zal
Will Will Wil
Must Muss Moet
May Mag Mag

2. Functions of MAVs (1)
The main function of modal verbs is to allow the speaker or writer to express their opinion of, or their attitude to a proposition.
These opinions or attitudes can cover a wide range of possibilities including obligation, permission, disapproval, giving advice, logical deduction, ability, possibility, and so on.

3. Functions of MAVs (2)
MAVS can be divided into two functional divisions:
one concerned with possibility and necessity in terms of freedom to act (including ability, permission and duty).
and the other (except "shall") are concerned with the theoretical possibility of propositions being true or not true, or probable or improbable.

4. Functions of MAVs (3)
Here are two interpretations of the MAV “must” according to an epistemic and deontic classification:
Epistemic (the knowledge of what constitutes “truth”)
You must be starving = you haven’t eaten all day….
Deontic (the study of “duty” or “right” and “wrong”)
You must do your homework = your teacher expects it ..
Ambiguous - You must speak Spanish:epistemic = obviously you speak Spanish having lived in Spain for ten years.deontic = you need to speak Spanish if you want to get a job in Spain.

5. Structure of MAVs (1)
MAVs occupy the first position in verb phrase, coming before any other auxiliary verb and/or the main lexical verb:
He should go to school.
He could have won if he practiced more.
MAVs are not declined:
I should, you should, he should, we should
The interrogative is formed by simply inverted with the subject of the sentence:
Should he go to school?
Could he have won if he practiced more?

6. Structure of MAVs (2)
The negative form carries the negative particle not (or n’t)
He can’t go to school.
He couldn’t have won if he practiced more.
MAVs are all followed by the base form of the verb without the addition of to.
I couldn’t (to) go to school.
He can’t (to) go to school.

7. Structure of MAVs (3) Association between MAVs
Will/won’t  Would/wouldn’t
Can/can’t  Could/couldn’t
Shall/shall not*  Should/shouldn’t
May/May not  Might/might not
Must
* Sometimes written as shan’t

8. Structure of MAVs (4)
Sometimes we can talk about remoteness in the attitude or mood
Less remote  More remote
Will/won’t  Would/wouldn’t
Can/can’t  Could/couldn’t
Shall/shall not*  Should/shouldn’t
May/May not  Might/might not
Must

9. Ought to – Have (got) to – Able to - Need to
Semi MAVs
Ought to – Have (got) to – Able to - Need to
You will notice that these semiMAV are made up of two or more separate words, the last one always being to.
They are all modal in meaning but not in form as they behave differently in a sentence from the pure modals.
We’ll look at semi-modals later.

10. Meaning of MAVs (1) I can/could help you (with your homework).
The problem with each modal verb is that it can have more that one meaning and the interpretation of a particular modal will depend heavily on the context.
The choice of MAV can also determine the degree or the nearness or remoteness of this attitude or mood.
I can/could help you (with your homework).
I will/would help you (with your homework).
I shall/should help you (with your homework).

11. Meaning of MAVs (2) Permission Physical Ability External Obligation
Physical Inability
Possibility
Approval
Impossibility
Absolute Certainty
Internal Obligation
Logical Deduction
Disapproval

12. Meaning of MAVs (3) He should be here by now. -- Logical Deduction
I could swim quite well when I was younger.
-- Physical Ability
You mustn't blame yourself for this.
-- Obligation
I might have won if I had tried harder.
-- Possibility
May I look at the questions now?
-- Permission
He must be French!
-- Logical Deduction
I must take my pills 3 time a day.
-- Obligation
You might have told me about it.
-- Disapproval….

13. Attitudes - Obligation (1)
The two main modals here are “must” and “have to”. The difference between them is usually given as follows:
Must is used to express an internal obligation that is imposed by the speaker.
Have to refers to rules and regulations that are imposed from outside the speaker (external obligation).

14. Attitudes - Obligation (2)
Inner Obligation
I must write to my mother.
I must do my homework.
External Obligation
I have to write to my mother.
I have to do my homework.
Must used in the –ve form expresses external obligation or prohibition
I mustn't talk to the bus driver.
I mustn’t talk in Mr Taylor’s English class.

15. Attitudes - Obligation (3)
The form that we use to express a lack of obligation is the negative of “need to” or “have to”, es.
He doesn't have to get up early.
I don’t have to do my homework.
He doesn't need to get up early.
She doesn’t have to do her homework.
There is no external constraint which determines if he has to get up at 7 o’clock or 8 o’clock.

16. Attitudes - Obligation (4)
Need (to) is a special verb since as a semiMAV it is almost always negative but it is also a lexical verb
Lexical verb (note the declination)
He needs to speak to you now.
I need to speak to you now.
Negative semiMAV
You don’t need to come to work tomorrow.
He doesn’t need to come to work tomorrow.
You don’t have to come to work tomorrow.
He doesn’t have to come to work tomorrow.

17. Attitudes - Logical Deduction (1)
Here we have to consider the certainty or remoteness that something is true or will happen.
The telephone rings: Certainty
That'll (will) be Frank. *****=
That must be Frank. *****=
That should be Frank. ***
That could be Frank. **
That might be Frank. *=
That may be Frank. *=

18. Attitudes - Logical Deduction (2)
That'll (will) be Frank.
He said he would ring three times – someone is ringing 3 times.
That must be Frank.
It’s four o’clock and the bell is ringing – Frank is due at 4.
That should be Frank.
I’m waiting for 2 people to come – but I heard Frank’s voice outside.
That could be Frank.
We are waiting for 6 different people - 3 have arrived but not Frank.
That might be Frank.
That may be Frank.
Who is it? I don’t know. I did bump into Frank and he said he’d come to see me.

19. Attitudes - Logical Deduction (3)
The modal verbs used here have been listed in what many consider to be the order of likelihood of something being true.
Both ends of the list are certain but in the middle, native speakers do not attribute such attention - but it gives you some idea of some of the choices available for making logical conclusions from situations.

20. Attitudes – Physical Ability (1)
The MAVs “can” and “could” are used, where “can” is more certain and “could” is more remote.
I can read….. (I speak Chinese)
I could read Chinese …(I don’t speak Chinese)..
…when I was younger and lived in China
…if someone had taught me it….
…if I had time to study it ….

21. Attitudes – Disapproval (1)
The MAVs “should” and “might” are used – with very little difference between the two form.
You should have told me
…it was your duty but you didn’t
You might have told me
… probably you forgot or didn’t think
or..
… perhaps you told me but I forgot…

22. Attitudes – Permission (1)
The MAVs “may” and “can” are used, (and less “might” and “could”).
You can go now.
You may go now.
Can/could you lend me your pen, please?
May (might*) I borrow your pen, please?
* Although correct, not often used by native speakers.
Student: Excuse me. Can I go to the toilet?
Teacher: Yes, you can but you may not.

23. Attitudes – Possibilty (1)
The MAVs “can/could” and “may/might” are used – with very little difference between the two form.
I can win the race (certain)
..most certainly I will win – I feel in fit….. I have trained a lot.
I could win the race (less certain)
..there is something wrong – probably something physical
*I may/might win (less certain)
..if I apply myself and I am lucky
*Most native speakers will not pay any difference to “may” and “might” in this context……

24. MAVS and Past Time (1)
We noted earlier that the pure modals do not change to show tense. Most of these modals do in fact have either present or future reference, but sometimes we need to refer back to the past.
One way to do this is to insert have immediately after the pure modal – (except for can which has its own past tense could when it refers to general ability).

25. MAVS and Past Time (2) I can speak German.
I could speak German (when I was seven years old).
You should see this film.
You should have seen this film.
Indonesia must be hot.
Indonesia must have been hot.
He could find his wallet.
He could have found his wallet.

26. SMAVs – be able to
We use this semi-modal to express possibility or the ability to do something, but unlike the pure modals, be able to has a full range of tenses and also needs to inflect to show agreement with its subject.
For example:
We were able to get in to see the film.
They haven't been able to find the missing document.
So, you aren't able to help.
I’ll be able to help you tomorrow.
It can also be accompanied by any of the pure modals:
I will be able to see you after lunch.
They might not be able to put us up for the night.

27. SMAVs – Have/has (got) to (1)
This is used to express necessity or obligation to do something
The have/has element is declined to agree with its subject.
the have/has got form is used only in the present and future tenses.
They have got to be more punctual.
He has got to take responsibility for the accident.
You don't have to come if you don't want to.

28. SMAVs – Have/has (got) to (2)
It also has its own past (had to – without “got”):
I had to help my father repair his car (past tense).
He didn't have to do all the shopping.(negative past tense).
It can be used with pure modals to show the attitude of the speaker (but without “got”):
We will have to put this off until tomorrow.
We might have to go back to pick up the stuff.
You shouldn't have to suffer in silence.

29. SMAVs – Ought to (1)
Usually, the meaning of “ought to” is the same as “should” whether it refers to giving advice or making a logical deduction.
Most native speakers attribute the same meaning to the following sentences:
You ought to see a doctor.
You should see a doctor.
Should you see a doctor?
They ought to have got back home by now.
They should have got back home by now.
They ought to drive carefully.
They should drive carefully.
They shouldn’t talk in class.
In practice, most speakers tend to prefer should for negatives and questions and ought for the affirmative.

30. Samples (1) He has to do his homework. He had to do his homework.
I can speak German.
I could speak German when I was seven.
You should see this film.
You should have seen this film.
Indonesia must be hot.
Indonesia must have been hot.
He could have found his wallet.
He is able to offer you the best price possible.
He must be French.
I must take my pills 3 times a day.

31. Samples (2) He ought to get up at nine o’clock.
I can't lift that suitcase by myself.
It might take more than a week.
May I look at the questions now?
She had to visit her mother.
She must visit her mother.
So, you can’t help me.
That can't be the right answer.
That can't have been the right answer.
That could be Frank.
That may be Frank.
That might be Frank.

32. Samples (3) That must be Frank. That should be Frank.
That'll be Frank.
They haven't been able to find the missing document.
They ought to drive carefully.
They ought to have got back home by now.
They say it may snow tomorrow.
They should drive carefully.
They should have got back home by now.
We were able to get in to see the film.
You have got to be there on time to get a seat.
You might have told me about it!

33. Samples (4) Could you..? You ought to ..? Shouldn’t you..?
You needn’t ..?
Can you..?
May I ..?
Must you..?
You have got to …..
You shouldn’t …
I might …
You needn’t …
They shouldn’t ..
He doesn’t have to…
We mustn’t…