English – Modal Verbs: Can, Could, Must, Should, May – BAC – Literary Stream

English – Modal Verbs: Can, Could, Must, Should, May – BAC – Literary Stream

Modal verbs are auxiliary verbs that express ability, possibility, permission, obligation, and advice. They are essential for the BAC English exam. This lesson covers the most common modals.

1. Can / Could

Can expresses ability in the present or general ability: “She can speak three languages.” / Permission: “Can I use your phone?”
Could expresses past ability: “I could swim when I was five.” / Polite request: “Could you help me, please?”

2. Must / Have to

Must expresses strong obligation (internal): “You must respect the law.” / Logical conclusion: “He has been driving for 10 hours. He must be tired.”
Have to expresses external obligation: “I have to wear a uniform at school.”
Mustn’t expresses prohibition: “You mustn’t smoke in hospitals.”
Don’t have to expresses absence of obligation: “You don’t have to come if you don’t want to.”

3. Should / Ought to

Express advice or recommendation:
“You should study harder for the exam.” / “You ought to see a doctor.”

4. May / Might

Express possibility or permission:
May: “It may rain later.” / “May I come in?” (formal permission)
Might: “She might be late.” (less certain than may)

Summary Table

Can/Could = ability (je peux/sais) | Must = obligation (je dois) | Should = advice (je devrais) | May = permission/possibility (il se peut que/je peux) | Might = weak possibility (il se pourrait que)

Exercises

Exercise 1: Complete: “You _____ brush your teeth twice a day. / _____ I open the window? / She _____ run very fast when she was young.”

Exercise 2: Rewrite using modals: “It is necessary to wear a helmet. / It is possible that he is at home. / I advise you to see a doctor.”

Exercise 3: Choose: “You (mustn’t / don’t have to) tell lies. / You (mustn’t / don’t have to) come to the party if you’re busy.”

See also Conditional Sentences and Passive Voice.