Modal verbs are a part of the larger category called auxiliary verbs which are verbs that cannot be used on their own. They need to be accompanied by another (main) verb. Sometimes modal verbs are called modal auxiliaries.
The following words are modal verbs: Can, Could, May, Might, Must, Shall, Should, Will, Would.
They are modal auxiliary verbs that provide additional information about the verb that follows it.
Modal verbs are used to express ability, obligation, permission, assumptions, probability and possibility, requests and offers, and advice. Each modal verb can have more than one meaning which depends on the context of that sentence (or question).
- You can go now. (= permission)
- I can play the guitar. (= ability)
Structure with Modal Verbs
A Modal verb is followed by another verb in the base form (the infinitive without the ‘To’) and they are not conjugated (we don’t add an ‘S’ in third person). See the following structure:
Subject + Modal Verb + Verb (base form of the infinitive)
- I can speak English (NOT: I can
- He can speak Spanish (NOT: He can speak
- She can speak Spanish (NOT: She can
Modal Verbs in Negative Sentences
Subject + Modal Verb + not + Verb (base form of the infinitive)
- You must not walk on the grass. (= You mustn’t walk on the grass.)
- He cannot speak Arabic. (= He can’t speak Arabic.)
- We should not be late. (= We shouldn’t be late.)
As you can see in the examples above, contractions of the Modal verb + not are normally possible.
The negative of can is cannot (‘not’ is joined to ‘can’) and the contraction is can’t
Modal Verbs in Questions
Modal Verb + Subject + Verb (base form of the infinitive)
- May I help you?
- Can I have another piece of cake please?
- Would you like to come with us?
Uses of Modal Verbs
Below we have a list of Modal verbs and the different uses of each with examples.
Source: Woodward English