1. his grandchildren’s books
2. Helen’s and Peter’s surname
3. this boy’s brother
4. the twins’ toys
5. these men’s professor
Объяснение:
1.The grand-children's books.
2. The Helen's and Peter's surname.
3. The boy's brother.
4. The twinse's toys.
5. The these men's profession.
1. his grandchildren’s books
2. Helen’s and Peter’s surname
3. this boy’s brother
4. the twins’ toys
5. these men’s professor
Объяснение:
1.The grand-children's books.
2. The Helen's and Peter's surname.
3. The boy's brother.
4. The twinse's toys.
5. The these men's profession.