1. This is Mary.This is her bicycle. This is Mary's bicycle.
2. This is Tom. This is his mother. This is Tom's mother.
3. Look at the boys.This is their ball. This is the boys' ball.
4. This is John. This is his house. This is John's house.
5. This is Sue. This is her sister. This is Sue's sister.
6. Look at the women. This is their car. This is the women's car.