must/mustn't, should/shouldn't

Children........spend a lot of time at the computer.

You ......clean your teeth every day.

You ......eat too many sweets and drink too much coffee.

Teenagers.............smoke or drink alcohol.

You ..........do your homework in time.

You ........study harder to get better marks.

Tom has had earache for two weeks! He ....... see a doctor.

Brian looks tired. He ...... work so hard.

People ..... plant more trees.

Peter has got a terrible headache. He.... listen to loud music.

Karen sprained her ankle yesterday and the doctor said that she ..... walk

People________ eat a lot of fruit to be healthy.