Modal verbs are used differently than normal verbs. They don't take an 's' for third person singular and questions are formed with inversion. They are followed directly by the infinitive form of another verb without "to." Modal verbs express abilities, habits, logical assumptions, possibilities, obligations, prohibitions, permissions, and polite requests. They include can, could, will, would, must, have to, should, ought to, need, may, might, mustn't, needn't, and don't have to. Each modal verb has specific meanings and uses depending on the context.

2. Modal verbs

4. Modals are different from normal
verbs:
• they don't use an 's' for the third person singular
• they make questions by inversion ('she can go' becomes 'can she
go?')
• they are followed directly by the infinitive of another verb (without
'to')

5. Ability
• Can/Could – when we talk about a skill or ability
For example: She can speak six languages. My grandfather could play
golf very well. I can’t drive.
Habits
• Will/Would– things we usually do, or did in the past
• For example: John will always be late! When I lived in Italy, we would
often eat in the restaurant next to my flat.

6. Logical assumptions/Deductions
• Must – Sure/Certain that something is true
For example: You must be exhausted!
• Can’t/couldn’t – Certain that something is not true/real
For example: That can’t be John, he is on holiday in Italy at the
moment.

7. Possibility
• Can + present infinitive – General possibility, something is theoretically
possible
For example: For the main course you can have pasta or pizza.
• Could/May/Might + present infinitive – It is possible/likely, used in a
specific situation
For example: You should keep that picture, it may be valuable one day.
Note: we can use can/could/might in questions BUT NOT may. Do you think you
can/could/might fix it?

8. Obligation/Duty/Necessity
• Must – especially when the speaker has decided that something is
necessary
For example: I must help her.
• Have to – especially when somebody other than the speaker has decided
that something is necessary
For example: We have to wear a uniform at school.
• Should/Ought to
For example: We should redecorate the living room soon.
• Need
For example: Need I finish the report today?

9. Absence of necessity
• Needn’t/Don’t have to/Don’t need to + present infinitive – it is not
necessary to do something
For example: You don’t need to take the dog for a walk, I will do it.
• Didn’t need to/Didn’t have to – in the past
For example: She didn’t need to/have to pay the whole amount today.

10. Prohibition
• Mustn’t/Can’t – it is forbidden to do something, it is against the
rules/law
For example: You mustn’t/can’t drive if you haven’t got a licence.
Permission
• Can/Could/May – to ask for and give permission
For example: Could I leave early today? May I open the window? Can
we swim in the lake?

11. Modal verbs: polite requests