When you got Covid-19.
[must see] [mustn't go]
When you’re in the cinema.
[must be] [mustn't take]
When you’re in the classroom.
[must turn ... off] [mustn't use]
When you’re driving a car.
[must drive] [mustn't drink]
When you talk with an adult.
[must be] [mustn't be]
When you’re on BTS skytrain.
[must stand] [mustn't take]
To save the world
[must plant] [mustn't pollute]
To be healthy
[must do] [mustn't drink]
To get grade 4 in this subject
[must do] [mustn't forget]
When you take the examination.
[must write] [mustn't copy]
When you use a social media.
[must post] [mustn't share]
When you need an iPhone 14 pro max.
[must save] [mustn't spend]
