This document provides examples of how to use the modal verbs "can", "could", "can't", "couldn't", "may", "might", and "must"/"mustn't" in sentences. It explains that "could" refers to ability or possibility in the past, while "can" refers to present ability. "Can't" and "couldn't" mean inability or impossibility. "May" can indicate permission, possibility, or formality in requests. "Might" suggests remote or uncertain possibility. "Must" expresses obligation and "mustn't" means prohibition. The document gives sentence examples and a quiz to practice using these modal verbs correctly.

2. I Could do…

3. • Could
• Could not
We use could not when we
did not have the possibility or
ability to do something in the
past.
We use could when we had
the possibility or ability to do
something in the past.
It is also used for requests.

4. Could you close the door,
please?  Request

5. When I was young I could not
swim.  Ability in the past

6. Now I can swim.  Ability now

7. When he was one year old he could
not read.

8. Now he can read.

9. When he was seven years old he
could not understand English

10. Now he can

11. Use the words: can, can't, could, couldn't
to complete the sentences
a. Bob_________ swim
but he__________ when he was two
years old.

12. b. When Steve was 6 years old, he
_______surf, but he is twenty now. He
_______.

13. c. Last week it was sunny and
we__________go swimming, but this
week we________. It was very cloudy and
windy.

14. d. Russell _____ play the violin, but he
________ play the piano.

15. e. Tony_________ cook now, but he
____________ before taking cooking
lessons.

16. f. Mary was so busy that she ________
accept the invitation to go out.

17. g. ___________ you please help me with
the science experiment?

19. May : Request (extremely formal)
May I use your phone?
Can I borrow your pencil? (informal)
Could I use your phone? (more formal)

20. May: Permission
You may (not) go outside.

21. May: probability
• It may rain tomorrow.

22. • She might be at home by now but it's not sure
at all.
Might: Remote possibility of
something

23. • I might not have time to go to the shop. I
have a lot of tests this week.

24. Circle the best modal for each sentence
I may/ can / might speak French well.
I may/ can / might see Brad Pitt when I am in Hollywood.
The Queen Elizabeth may not / can not / might not visit
our country.
May/ Can/ Might I close the door?
I can/ may / might go on holiday to Spain.

25. • You never know, I may/ might become a
President one day.
• Billy and I may/might cook dinner tonight.
• You might / may leave if you wish.

26. Answer Key 
• Can
• Might
• Might not
• May
• May
• Might
• May
• May

27. Is it possible or not so possible to
happen?

28. Make questions with ‘may’
according to the situations

30. Must: Express obligation (generally
they are strong rules)

31. Mustn’t: Prohibition

33. Answer Key 
• D
• C
• B
• D
• A
• A
• B
• A
• C
• D

34. Write sentences with ‘must’ or ‘mustn’t’
according to the class rules.

35. Make a list of the things you MUST or MUSTN’T
do in a zoo. Write complete sentences.
BUY A TICKET – FEED THE ANIMALS – TOUCH THE ANIMALS –
TAKE PHOTOS – BE QUIET – SHOUT – DROP THE LITTER
MUST DO MUSTN’T DO
-You… -You…