must/mustn"t, should/shouldn"t

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

We .......keep our planet clean!

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

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

You .........skip breakfast, because it`s very important for your health.

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

You ... drink a cup of milk every day

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

Teenagers...........be rude to their parents.

You .......make noise at the library.

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

You .......use your phones at the lessons.

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

If you've got a fever, you ......... go to school. You ..... stay in bed.

- I need to lose weight. What ..... I do?

- Well, you....... go on a diet and you...... take up a sport.

Brian looks tired. He ...... works so hard.

People ...... cut down trees. They ...... plant more trees.

You ........lie to your parents or your friends.

Speak nicely to the shop assistant. You ..... be rude!

Bob can't sleep very well at night. He ..... drink much coffe. He ....... see a doctor.

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

Deborah has got a really bad cough. She ...... go on a skiing trip

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

People________ eat a lot of fruit to be healthy.