Modals are special verbs that help us express ability, possibility, permission, advice, and necessity or obligation.
In this post, you’ll learn how to use modals in English modals correctly in affirmative, negative, and contracted forms.
1. Can and Be Able To – Expressing Ability
We use ‘can’ and ‘be able to’ to talk about ability.
Affirmative:
Subject + can + base form
Subject + am/is/are + can + base form
Negative:
Subject + cannot + base form
Subject + am/is/are + not + base form
Contractions:
cannot → can’t; is not → isn’t; are not → aren’t
Examples:
- I can swim very fast.
- She is able to drive a car.
- We can’t speak Japanese.
- He isn’t able to lift that box.
2. Can – Expressing Possibility
We also use ‘can’ to show that something is possible in general.
Affirmative:
Subject + can + base verb
Negative:
Subject + cannot (can’t) + base verb
Contraction:
cannot → can’t
Examples:
- It can be hot in Texas in summer.
- That restaurant can get very busy.
- It can’t be easy to work and take English classes!
3. Can or Be Allowed To – Asking for and Giving Permission
We use ‘can’ or ‘be allowed to’ to talk about permission.
The negative form shows prohibition (something you are not allowed to do).
Affirmative:
Subject + can / am, is, are + allowed to + base verb
Negative:
Subject + cannot (can’t) / am not, isn’t, aren’t + allowed to + base verb
Contractions:
cannot → can’t; is not → isn’t; are not → aren’t
Examples:
- Can I leave class early today? (asking for permission)
- You can park here. (giving permission)
- Students are allowed to use their phones during break. (giving permission)
- You can’t smoke in the classroom. (prohibition)
- We aren’t allowed to eat in the library. (prohibition)
4. Should – Giving Advice
We use ‘should’ to give advice or recommendations.
Affirmative:
Subject + should + base verb
Negative:
Subject + should not (shouldn’t) + base verb
Contraction:
should not → shouldn’t
Examples:
- You should study every day.
- He should eat more vegetables.
- They shouldn’t stay up too late.
5. Must and Have To – Expressing Necessity or Obligation
We use ‘must’ or ‘have to’ to talk about something that is necessary or required.
Affirmative:
Subject + must / have to + base verb
Negative:
Subject + must not (mustn’t) / do not (don’t) have to + base verb
Contractions:
must not → mustn’t; do not → don’t
Examples:
- You must wear a seatbelt.
- We have to do our homework.
- You mustn’t touch that wire!
- They don’t have to work on Sunday.
6. Must Not vs. Not Have To
Be careful! These two have very different meanings:
- Must not (mustn’t) = It’s not allowed / It’s forbidden.
- Not have to = It’s not necessary.
Examples:
- You mustn’t be late. (It’s forbidden.)
- You don’t have to come early. (It’s not necessary.)
7. May and Might – Possibility in the Future
We use ‘may’ and ‘might’ to show that something is possible but not certain in the future.
Affirmative:
Subject + may / might + base verb
Negative:
Subject + may not / might not + base verb
Examples:
- I may go to the party.
- It might rain tomorrow.
- She may not come tonight.
8. Will – Certainty in the Future
We use ‘will’ to talk about something we are sure will happen in the future.
Affirmative:
Subject + will + base verb
Negative:
Subject + will not (won’t) + base verb
Contractions:
I will → I’ll; He will → He’ll; She will → She’ll; It will → It’ll; They will → They’ll; We will → We’ll; will not → won’t
Examples:
- She will graduate next year.
- They won’t forget your birthday.
- I’ll call you tomorrow.
Common Mistakes with Modals in English
✅ She can sing.
❌ He doesn’t can drive.
✅ He can’t drive.
❌ You must to wear a helmet.
✅ You must wear a helmet.
❌ They don’t must work today.
✅ They don’t have to work today.
Quick Review of Modals in English
| Modal | Use | Example |
|---|---|---|
| Can / Be able to | Ability | I can play the piano. |
| Can / Be allowed to | Permission | We can go out now. |
| Should | Advice | You should rest. |
| Must / Have to | Necessity | You must study. |
| Must not | Prohibition | You mustn’t smoke. |
| Not have to | Not necessary | You don’t have to come. |
| May / Might | Possibility | It might rain. |
| Will | Certainty | I will call you. |
Let’s Practice Modals in English!
Exercise A
Choose the correct modal for each sentence.
1. I _______ swim very fast.
a) am able
b) can
c) should
2. He _______ wear a uniform at work. It’s the rule.
a) must
b) can
c) might
3. You _______ eat in the classroom. It’s not allowed.
a) don’t have to
b) mustn’t
c) might not
4. They _______ come to the meeting if they are busy. It’s not necessary.
a) must not
b) don’t have to
c) shouldn’t
5. We _______ use our phones during the test.
a) can
b) are allowed to
c) aren’t allowed to
6. You _______ study more if you want to pass the test.
a) should
b) might
c) can
7. I _______ play the guitar, but not very well.
a) should
b) can
c) must
8. It _______ rain tomorrow, so take an umbrella.
a) must
b) might
c) should
9. You _______ smoke here. It’s forbidden.
a) don’t have to
b) must not
c) may
10. She _______ call you later. She promised.
a) will
b) might
c) should
Exercise B
Read each sentence carefully. There is one mistake in every sentence.
Rewrite the sentence correctly.
1. Alejandra can swims very fast.
2. You must wears your ID card at school.
3. He don’t can drive a car.
4. Diego and Frida are can speak three languages.
5. You do must study tonight.
6. Students mustn’t to eat in class.
7. You should to drink more water.
8. She mights go to the party tonight.
9. He willn’t come tomorrow.
10. We are able to can play the piano.
Scoring and Feedback
🔵 17 – 20 Correct
Excellent work! 🎉You really understand Modals. Keep using it in your everyday conversations and writing.
🟢 14 – 16 Correct
Great job! ✅ You have a good understanding of Modals. Review the ones you missed.
🟡 12 – 13 Correct
Good effort! 💪You’re learning, and that’s what matters. Take a moment to review the examples and do the quiz again.
🔴 0 – 11 Correct
No worries! 🌱 Modals can be tricky at first. Go back and review the examples in the lesson.
Modals are short words with powerful meanings! When you learn how to use modals in English, you can talk confidently with other people!
Remember! Learning a language is not about perfection—it’s about progress. Keep practicing, stay curious, and trust the process. You are moving beyond English to more opportunities, connections, and self-expression!