S + must/ mustn't + Vo + O: Ai phải/cấm làm gì...

`1.` You must finish your homework tonight.

`2.` We must wear uniform when we go to school.

`3.` He must get up at 6 o'clock every day.

`4.` She must learn English at the weekend.

`5.` I must take care of my brother.

`6.` You mustn't smoke in the living room.

`7.` Students mustn't use smartphones in the class.

`8.` I mustn't go out at 10 p.m

`9.` You mustn't watch TV until I finish my homework.

`10.` He mustn't play video games too much.