Составить 15 предложений в претежательном падеже. . по

1) the sportsman's T-short
2) the roof of the buiconcert 
3) the beginning of the concert 
4) the growth of the company.
5)Mary's toy
6) the dog's collar
7) My old friend John's brother is an engineer
8) Mary is the sister of my brother's wife 
9) Did you take the books of the students?
10) the sister of my neigh
11) the room of the doctor 
12) the children's tickets
13) the teacher's bag 
14) the teacher's bag
15) Peter's friends