Before you read the dialogue, look at the picture and guess what the problem is.
John: My head hurts. I can’t concentrate on this exercise.
Jane: What is the problem?
John: I think it’s because I can’t sleep well lately.
Jane: You mustn’t stay up late. You must learn to sleep early, it’s healthy and good for the mind and body.
John: Yeah, I will try to sleep early, thanks for the advice. Can you help me complete this exercise? I can’t do it like this.
Jane: Don’t worry, I can help so you can go and have some rest.
John: Thanks for the help, Jane.
Jane: You’re very welcome! I hope you feel better.
Ability & Permission
CAN is used to show that someone has the ability to do something, or to ask for/give permission.
- Ability: "I can speak English." / "I can help you."
- Permission: "Can I leave early?"
CAN'T (Cannot) shows inability or lack of permission.
- "I can't concentrate today."
- "You can't use your phone during the exam."
Obligation & Prohibition
MUST is used to express a strong obligation, a rule, or something that is highly necessary.
- "You must sleep early for your health."
- "Students must do their homework."
MUSTN'T (Must not) is used for strict prohibition. It means "Do not do this."
- "You mustn't stay up late."
- "We mustn't talk loudly in the library."
A. True or False (Based on the dialogue)
1. John can't sleep well lately.
2. Jane tells John he must stay up late.
3. Jane refuses to help John with the exercise.
B. Fill in the blanks
Choose can, can't, must, or mustn't.
1.
I leave early today? I feel sick.
2. I'm sorry, but I
do this exercise. It's too hard.
3. Children
play outside at midnight. It's dangerous.
4. You
take care of your health!
C. Writing Task
Write 3-4 sentences responding to these situations using modals:
- Ask your teacher for permission to go home.
- Tell your friend they are prohibited from using a phone in class.
- Show you have the ability to help with homework.