Скажите, что вы должны (не должны) делать. Можете использовать следующее: help your mother about the house; 50 shopping;

I must help my mother about the house.

I must go shopping.

I must look after my pet.

I must come to school on time.

I must take my dog for a walk.

I must feed my pet.

I must do exercises every clay.

I must wash my hands before I eat.

I mustn’t get up too late.

I mustn’t eat too much ice cream.

I mustn’t be late for school.

I mustn’t watch TV too late.

I mustn\'t go to bed too late.