1. You are expecting david to ring. the phone rings (must)

=>That must be david who rings the phone.

2. Anna is a better runner than Rula. you think Anna will probably win the race tomorrow(should)

=>Anna should win the race tomorrow.

3. A letter ar rives. it is possible that it is from your cousin Janice (could)

=>The letter could be from my cousin Janice.

4. there is a knock at the door. your mum says ít might be Colin, but you know Colin is on holiday(can't)

=>That can't be Colin because he is on holiday.

5. you see someone wearing a costume. you think there is a strong probability that she is going to a fancy-dress party(must)

=>She must be going to a fancy dress party.

6. your sister is looking for her hairbrush. you think it is possible that it is in the living room(might)

=>Your hairbrush might be in the living room.

7. you are waiting for Harriet to arrive. you think she will probably be there in half an hour(should)

=>Harriet should be here in half an hour.

8. you are talking about why James seems to be sad. you think it is possible he is in trouble at school(could)

=>James could be in trouble at school.

$1,$

→ That must be david who rings the phone

$2,$

→ Anna should win the race tomorrow

$3.$

→ The letter could be from my cousin Janice

$4.$

→ That can't be Colin because he is on holiday

$5.$

→ She must be going to a fancy dress party

$6.$

→ Your hairbrush might be in the living room

$7.$

→ Harriet should be here in half an hour

$8.$

→ James could be in trouble at school