English – Grammar: Modal Verbs Can Cannot Must Must Not – 1st Year Middle School – Algerian Curriculum

Modal Verbs: Can, Cannot, Must, Must Not

1. Can / Can’t (ability and permission)

Ability: I can swim. She can speak English. He can’t (cannot) ride a bike.
Permission: Can I go to the toilet? You can sit here.

2. Must / Mustn’t (obligation and prohibition)

Obligation: You must do your homework. Students must wear a uniform.
Prohibition: You mustn’t eat in class. You mustn’t run in the corridor.

3. Formation

Modal + base verb (without to): I can swim. (NOT: I can to swim)
Modal verbs don’t change for he/she/it: He can swim. (NOT: He cans swim)

4. Exercises

Exercise 1: Complete: I _____ (can) speak Arabic. You _____ (must) be quiet in class. She _____ (can’t) play the piano.

Exercise 2: Make rules for the classroom using must/mustn’t (5 rules).

See also: Modal Verbs.