Modal Verbs Exercises
How modal verbs work
Modal verbs (can, could, may, might, must, should, will, would) add meaning like ability, permission, obligation or probability to another verb — and they follow special grammar rules.
- Form:
- modal + base verb: She can swim (never 'to swim' or 'swims')
- No -s / no do:
- He must go (not 'musts'); negatives and questions without 'do': Can you…? You shouldn't…
- Ability:
- can / could: I can drive. She could read at age four.
- Obligation:
- must / have to: You must wear a seatbelt. | Prohibition: mustn't
- Advice:
- should / shouldn't: You should see a doctor.
- Possibility:
- may / might / could: It might rain later.
Examples
She can speak three languages fluently.
ability
You must fasten your seatbelt during take-off.
strong obligation (rule)
You shouldn't drink so much coffee before bed.
negative advice
It might snow tonight, so drive carefully.
possibility, not certain
May I use your phone for a minute?
polite permission
Practice exercises
Choose the correct modal
Select the modal verb that best fits each situation.
1.You ___ smoke in the hospital — it's strictly forbidden.
2.I ___ ride a bike when I was five years old.
3.You look exhausted. You ___ take a day off.
4.It's a holiday tomorrow, so I ___ get up early.
5.Take an umbrella — it ___ rain this afternoon.
Complete the sentences
Type the missing modal verb (can, can't, must, mustn't, should, shouldn't, might...).
Put the words in order
Click the words in the correct order to build the sentence.
11. Build the sentence:
12. Build the sentence:
13. Build the sentence:
14. Build the sentence:
True or false?
Decide if each statement about modal verbs is true or false.
15."She cans speak Italian" is correct English.
16.'Mustn't' and 'don't have to' mean the same thing.
17.After a modal verb, we use the base form of the verb without 'to'.
18.'Might' expresses a smaller probability than 'will'.
Frequently asked questions
What are the modal verbs in English?
The core modal verbs are can, could, may, might, must, shall, should, will and would. Semi-modals like have to, ought to and need to behave similarly in meaning but not always in grammar.
What is the difference between 'must' and 'have to'?
Both express strong obligation and are often interchangeable. 'Must' tends to express the speaker's own authority or urgency (I must finish this today), while 'have to' points to external rules (I have to wear a uniform at work). The key contrast is in the negative: 'mustn't' = forbidden, 'don't have to' = not necessary.
Why can't I say 'She cans' or 'He musts'?
Modal verbs are grammatically fixed: they never take -s, never use 'do' for questions or negatives, and are always followed by the base form of the main verb. That's what makes them 'modals' rather than normal verbs.
What is the difference between 'may', 'might' and 'could' for possibility?
All three express present or future possibility and are close in meaning. 'Might' often suggests slightly less certainty than 'may'; 'could' emphasises that something is one of several possibilities. In everyday speech they are largely interchangeable.
How do I make questions with modal verbs?
Invert the modal and the subject — no 'do' needed: Can you drive? Should we wait? May I come in? The main verb stays in its base form.
Modal verbs explained in depth
Modal verbs are small words with big responsibilities. With a single syllable, English speakers signal whether something is possible, necessary, allowed, forbidden or advisable. Because so much social meaning is packed into them — politeness, authority, doubt — using the wrong modal doesn't just sound ungrammatical; it can sound rude or change what you're saying entirely.
Grammatically, modals form a closed club with strict rules: no third-person -s, no infinitive 'to' after them, no combining with 'do' in questions and negatives, and no past participle forms. This is actually good news for learners — once you internalise 'modal + base verb', the mechanics never change. All the difficulty lives in choosing the right modal for the meaning.
The meaning map has three main territories. Ability and permission belong to can/could/may: 'I can swim' (ability), 'Could I leave early?' (permission). Obligation belongs to must and have to, with the crucial negative asymmetry that trips up almost every learner: 'You mustn't tell anyone' forbids telling, while 'You don't have to tell anyone' merely makes telling optional. Probability belongs to may/might/could for possibility and must/can't for logical deduction: 'She must be home — her lights are on.'
'Should' deserves its own mention as the advice modal. It is softer than must, which is why doctors, teachers and friends reach for it constantly: 'You should rest.' Its negative, 'shouldn't', warns without forbidding. In formal writing, 'ought to' is an equivalent, though far less common.
When practising, focus on contrasting pairs in context: mustn't vs don't have to, can vs might, should vs must. The exercises on this page are built around exactly those contrasts, because choosing between two similar modals — not forming them — is where real-world mistakes happen.