Read these sentences and fill in the gaps with the correct variant (must, mustn’t, have to, don’t have to, doesn’t have to or has to).
1. I can give you my car, so you buy a new one.
2. You return these shoes. They are too small for you.
3. Students look at their notes during the test.
2)did they take English lessons last year?
3) he won't work in the library.
4)I'm sure that he will often write letters to his parents.
5) is he reading a book now?
6) my children were sleeping when I came home.
7) while I was cooking dinner my parents were watching tv
8)he will be studing in the library from 12 pm till 5 pm
9) he hasn't written an article yet
10) he told that he had prepared for exam well
11)I have been waiting for you for 20 minutes
12)he had been studing English last year for 5 months
13)he will have been working here for 20 years on 1st of June