đáp án của mình:
1.This is Nam's book.

2.The mason's tool was heavy.

3.She prepared the children's outfit.

4.The boy's coat was torn.

5.Mr. Van is Mr. Dong's friend.

6.The pupils' desks are always clean.

7.The windows of the house are green.

8.The boys' caps are on the shelves

9.He likes to read John Keats' poems.

1.This is the book of Nam
→This is Nam's book.

2.the box of the man was heavy
→The mason's tool was heavy.

3.She prepared the outfit of her children
→She prepared the children's outfit.

4.The coats of the boys were torn
→The boy's coat was torn.

5.We're going to the house of my mother
→Mr. Van is Mr. Dong's friend.

6.
→The pupils' desks are always clean.

7.the desks of the pupils are always clean
→The windows of the house are green.

8.The caps of the boys are on the shelves
→The boys' caps are on the shelves

9.He likes to read the poems of John Keats
→He likes to read John Keats' poems.

1.→This is Nam's book.

2.→The mason's tool was heavy.

3.→She prepared the children's outfit.

4.→The boy's coat was torn.

5.→Mr. Van is Mr. Dong's friend.

6.→The pupils' desks are always clean.

7.→The windows of the house are green.

8.→The boys' caps are on the shelves

9.→He likes to read John Keats' poems.