Question

1. you (модальный глагол) use the office phone for private talk. 2. you (модальный глагол) come if you don`t want to. 3. i know you are a careful driver but you (модальный глагол) drive so fast. 4. schoolchildren (модальный глагол) wear jewelllery when at school.

Answer 1

You can use the office phone for private talk
you cant come if you dont want to
I know you are a careful driver but you mustnt drive so fast.
school children should wear jewellery when at school

Answer 2

1 Must
2 can
3 needn't
4 must