Modal Verbs — Advice, Possibility, Obligation

Modal Verbs — Advice, Possibility, Obligation

B1 Intermediate⏱ 5 minutesGrammarLesson 12 of 30
📖 From My Life

When I started learning French at 35 in La Réunion, my tutor looked at me on day one and said: “You should practise every day. You must speak even when you make mistakes. And you can do this — I have seen adults reach C1.”

She was right on all three counts. But notice how much work those three little verbs did. In one breath she gave me advice, stated an obligation, and expressed ability. Modal verbs are the steering wheel of English — small words that change the direction of everything around them.

🎯 Language Focus

Function Modals Example
Obligation / rule must, have to “You must complete the form before Friday.”
Advice should, ought to “You should practise a little every day.”
Possibility might, could, may “It might be difficult at first.”
Ability can, could (past) “I can speak four languages.”
No obligation don’t have to “You don’t have to come — it’s optional.”
Prohibition mustn’t “You mustn’t smoke here.”
⚠️ The classic B1 trap: mustn’t and don’t have to are NOT the same. “You mustn’t speak” = it is forbidden. “You don’t have to speak” = you can, but it isn’t required.
🔊 Say it right: in natural speech, modals are weak and quick — “you shud practise”, “I kun do it”. Never stress the modal unless you are correcting someone: “You SHOULD practise!”

✏️ Quick Practice — Try It, Then Check

1. Obligation or advice? “You must wear a seatbelt.”
Obligation ✓ — it’s the law, not my opinion.
2. Fill the gap: “You ___ try the local food — it’s amazing!” (advice)
should ✓ — a recommendation, not a rule.
3. Fill the gap: “She ___ be at home — I’m not sure.” (possibility)
might / could / may ✓ — all three work for uncertain possibility.
4. Which is correct? a) “You don’t have to smoke here.” b) “You mustn’t smoke here.”
(b) ✓ — smoking is prohibited. “Don’t have to” would mean smoking is optional, which makes no sense here.
5. Rewrite with a modal: “It is necessary to book in advance.”
“You must / have to book in advance.” ✓
6. True or false? “Could” can express both past ability and present possibility.
True ✓ — “I could swim at five” (past ability) vs “It could rain later” (present possibility).
7. Your tutor says: “You should to practise more.” Find the mistake.
should practise ✓ — modals are followed by the bare infinitive, never “to”. (Exception: ought to.)
8. Write one sentence: give advice to a new English learner.
Example: “You should speak English every day, even if only to yourself.” ✓ Any should / ought to + bare infinitive sentence works.

🗣️ Your Turn (60 seconds)

Think of someone learning a new skill — cooking, driving, a language. Say three sentences out loud: one obligation (must), one piece of advice (should), one possibility (might). Example: “You must practise regularly. You should record yourself. It might feel strange at first.”

💡 Your 5-Minute Takeaway

Must = obligation (rule). Should = advice (opinion). Might = possibility (not sure). Can = ability. Master these four and you control 90% of modal situations at B1. And remember: mustn’t (forbidden) is not don’t have to (optional).

Independent educational resource. Not affiliated with, endorsed by, or accredited by Cambridge University Press & Assessment. Confers no qualification. Grammar reference: Swan, Practical English Usage. Frameworks: PPP, TBLT, ESA (standard ELT methodology).

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