Unit 5.1

Can: Modals of Ability

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A modal verb is a type of auxiliary (helping) verb that has no meaning on its own but it modifies the main verb, changes its meaning and gives more details about the action.

The verb can is a modal verb used to express the idea of ability or opportunity, to express the possibility or impossibility of an event or action happening and to ask for or give permission.


The modal verb can is used as an auxiliary verb and has three forms: affirmative, negative and interrogative.


Its structure, in the affirmative form, is:
Subject + can + verb + …

Subject can Verb
I can work
You can work
He can work
She can work
It can work
We can work
You can work
They can work


Its structure, in the negative form, is:
Subject + cannot + verb + …

  • Short form of the negative form is can’t;
  • Can is an exception in forming the negative form and it is written together with not: cannot (can not is incorrect).
Subject cannot Verb
I cannot work
You cannot work
He cannot work
She cannot work
It cannot work
We cannot work
You cannot work
They cannot work


Its structure, in the interrogative form, is:
Can + subject + verb + …?

Modal Verb Subject Verb Question Mark
Can I work ?
Can you work ?
Can he work ?
Can she work ?
Can it work ?
Can we work ?
Can you work ?
Can they work ?


  1. I can play the piano.
    She cannot play the guitar.
  2. Parks can be dangerous.
    Sloths cannot move fast.
  3. I can help you with your homework.
    Can we help you and your husband?
  4. We can stay at his place for a week!
    You cannot come with us.
  5. My children can go to the party.
    Can I have a swim?
  6. My wife can go to Milan this summer.
    I cannot go on holiday because I have to work.
  7. You can’t always get what you want. 
    Can you just shut up and listen?
  8. Can you write down your telephone number, please?


We use can when we express:

  1. abilities: to be able to do something;
  2. general truths: to talk about things that are usually true;
  3. offers: to make offers;
  4. opportunities: to express the chance to do something;
  5. permissions: to ask or give permission;
  6. possibilities: to talk about possible situations;
  7. reproaches: to criticise someone’s actions;
  8. requests: to demand something.


The modal verb can expresses ability, offer, request, possibility, opportunity, permission, reproach and general truth.

We can use it in its different forms:

  • affirmative: we start with the subject followed by can and the verb.
  • negative: we start with the subject followed by cannot and the verb.
  • interrogative: we start with can followed by the subject and the verb (the sentence ends with a question mark).

For example:
— Affirmative: “She can play the piano.”
— Negative: “She can’t play the piano.”
— Interrogative: “Can she play the piano?

NOTE: The form is always the same, even for the third person singular.

Let’s revise this content within the {Form} section. Take a look at the {Example} section that shows its use within a context.


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