Modal verbs, also called auxiliary verbs, are used to express likelihood, permission, ability or obligation. They cannot stand alone, they are always used with other verbs. Modal verbs include can, could, must, may, might, will, would, should.
Modal verb: Can
Use can to say that
- something is possible
- to make requests
- ask or give permission
- to say that someboday has the ability to do something.
- Summer in Thailand can be very hot.
- Can you make me a tea?
- You can stay with us for the night.
- I can speak English.
To make a negative sentence with can, use: can’t or cannot
- I can’t speak English.
- You cannot stay with us.
To create questions, simply bring the modal verb before the subject:
- Can you speak English?
- Can I stay with you for the night?
Modal verbs: Could
Could can be used
- as the past tense of can
- to say that something may be possible in the future (not certain)
- to make polite requests
- When I was 5 I could play the piano.
- If you don’t hurry, you could be late for school. (not sure)
- could you pass me the salt please?
To make a negative sentence with could, use: could not or couldn’t: When I was 5 I couldn’t play the piano.
To create questions, simply bring the modal verb before the subject: Could you help me?