Can and Can’t

What does 'can' mean?

Ability — She can swim very fast.

Inability — I can’t play the piano.

Permission — Can I use your phone?

Form

Rule — can + base verb (same for all subjects)

Positive — I / She / They can swim.

Negative — I / She / They can’t swim.

Question — Can you / she / they swim?

Warning — Never: ‘can to swim’ or ‘cans’

Short answers

Yes — Yes, I can.

No — No, I can’t.

Example — Can you cook? — Yes, I can.

Recap

Positive — can + base verb

Negative — can’t / cannot + base verb

Question — Can + subject + base verb?

Rule — No -s ever — She can (NOT cans)

Can and Can’t — Exercises

Choose the correct answer

Circle the correct option.

1. Fish _____ breathe underwater. (can't / can / cans)
2. I _____ fly without a plane. (can / cans / can't)
3. She _____ speak three languages. (can't / cans / can)
4. Babies _____ walk when they are born. (can / cans / can't)
5. _____ you help me? (Cans / Is / Can)

Fill in the blank

Write the correct word.

1. My sister   read — she’s only two.
2. He   play the guitar very well.
3.   I open the window?
4. Cats   see in the dark.
5. They   come — they’re busy.

Can and Can’t — Answer Key

Choose the correct answer

1. can — It is something fish are able to do → can. Never "cans".
2. can't — People are not able to fly without a plane → can't.
3. can — Ability → can. Modal verbs never take -s: she can, NOT she cans.
4. can't — Babies are not able to walk when they are born → can't.
5. Can — Questions start with Can: Can you help me? Never "Cans" or "Is".

Fill in the blank

1. can't
2. can
3. Can
4. can
5. can't