The words can, could, may, might, will, would, shall, should, must and ought are modal auxiliary verbs. Sometimes the verbs need and dare are also used as modal auxiliaries.

Modal auxiliary verbs are followed by an infinitive without to. Ought is an exception to this rule. It is followed by an infinitive with to.

• I can swim. (NOT I can to swim.)
• You should apologize.
• You ought to apologize.
• They will arrive.

Questions and negatives are made without do.

• Can you swim? (NOT Do you can swim.)
• She will not come. (NOT She do not will come.)

Modal auxiliary verbs express ideas such as necessity, obligation, permission, possibility, ability etc.

Complete certainty

• I will be working late tonight.
• She will be here soon.
• That must be a fox.
• That can’t be your uncle.

Possibility / probability

• If she left home in the morning, she should / ought to be here soon.
• We may go camping on the weekend.
• It may rain in the afternoon.

Weak probability

• I might pass the test.
• It might rain in the afternoon.

Theoretical / habitual possibility

• Kerala can be quite warm in summer.
• Glass can be blown.
• Snakebite can kill people.

Strong obligation

• You must report at 6 am.
• All students must be present on Monday.
• You must get that mole checked.

Prohibition

• You must not be late.
• You can’t leave now.
• She must not reveal this to anyone.

Can you use modals correctly?

Modals exercise 1

Fill in the blanks with an appropriate modal auxiliary verb.

1. I don’t think that I ………………………… pass the test. (will / would / can)

2. If you improve your communication skills, you …………………………. get a better job. (will / would / could)

3. If we don’t get the money what ……………………………. we do? (will / would / could)

4. You …………………………….. have locked the door before going out. (should / would / can)

5. He ………………………….. not come unless you invite him. (will / would / could)

6. …………………………. we depend on them? (Can / Will / Would)

7. …………………………. I do the washing up? (Shall / Should / Would)

8. …………………………… you open the window? (Can / Shall / Should)

9. Where ……………………………. they have gone? (should / could / would)

10. If you had run faster, you …………………………….. have won. (will / could / should)

11. If I lose the job, we  ………………………….. be in trouble. (will / would / could)

12. …………………………. I open the window? (Will / Shall / Would)

13. If you worked harder, you ……………………………. pass the test. (would / will / should)

14. ………………………….. you like something to drink? (Would / Could / Should)

15. …………………………. I know who you are. (May / Can / Will)

16. Where ………………………….. I buy used laptops? (can / may / will)

17. He promised that he …………………………. help me. (would / might / should)

18. If you don’t leave, I ………………………… call the police. (will / must / would)

19. Every weekend, they ………………………… go swimming. (would / might / need)

20. ………………………. I book tickets in advance? (Need / Will / Shall)

21. ………………………. you mind waiting for a minute? (Would / Should / Could)

Answers

1. will, 2. will, 3. will, 4. should (Use should have + past participle to criticize people for not doing things.), 5. will, 6. Can, 7. Should, 8. Can, 9. could, 10. could (Use could have + past participle to talk about unrealized past ability.), 11. will (Use will to make future predictions.), 12. Shall (Use shall I/we to ask for suggestion or recommendation.), 13. would, 14. Would (Use would in polite offers.), 15. May (Use may to ask for permission.), 16. can, 17. would, 18. will, 19. would, 20. Need, 21. Would