Modal Verbs — can, can't, must, mustn't

A1 Beginner · Lesson 2
CAN

Use can to talk about ability — things you are able to do.

+My brother can play the guitar.
+Dogs can hear sounds that humans cannot.
✏️ Form: subject + can + verb (base form)
⚠️ Can is the same for all subjects — no –s with he/she/it!
CAN'T

Use can't to talk about inability — things you are not able to do.

–She can't ride a bike yet.
–I can't understand this question.
✏️ Form: subject + can't + verb (base form)
MUST

Use must for strong obligations and rules — things that are necessary.

+You must wash your hands before cooking.
+All staff must carry their ID card.
✏️ Form: subject + must + verb (base form)
MUSTN'T

Use mustn't for prohibition — things that are not allowed.

–You mustn't use your phone while driving.
–Visitors mustn't touch the artwork.
✏️ Form: subject + mustn't + verb (base form)
⚠️ Mustn't = forbidden. It is NOT the same as don't have to (not necessary).

Quick Summary

ModalMeaningExample
canabilityShe can run fast.
can'tinabilityHe can't cook.
mustobligation / ruleYou must stop here.
mustn'tprohibitionYou mustn't litter.

Exercise 1 — True or False?

Read each statement. Choose True or False.

Exercise 2 — Multiple Choice

Choose the correct modal verb to complete each sentence.

Exercise 3 — Matching

Match each sentence to the correct meaning.

Exercise 4 — Gap Fill

Choose the correct modal verb from the dropdown to complete each sentence.

Exercise 5 — Word Order

Click the words to build the sentence in the correct order. Click a placed word to remove it.

Exercise 6 — Word Sort

Click a category box first, then click the sentence to place it there. Click a placed sentence to remove it.

✅ Ability

❌ Inability

📋 Obligation

🚫 Prohibition

Exercise 7 — Complete the Conversation

Choose the correct modal verb to complete the conversation.

🏆 Your Scores

Exercise 1 — True / False–
Exercise 2 — Multiple Choice–
Exercise 3 — Matching–
Exercise 4 — Gap Fill–
Exercise 5 — Word Order–
Exercise 6 — Word Sort–
Exercise 7 — Conversation–