Must/Should

You            use your mobile phone in the classroom.

It’s hot. They             open the window. 

You             watch TV all night.

I             give the dog some water. He’s thirsty.

Stop it! You             be rude to people.

     You             call your parents. They’re worried.

 I             go home now. It’s late.

We             be late for school.

He             brush his teeth twice a day. 

They            drop rubbish (сміття).