Выполним задание, раскрыв сокращенные формы.
- What's this? - What is this?
- It's Daddy's. - It is Daddy's.
- That's my doll. - That is my doll.
- They're Mum's. - They are Mum's.
- What's wrong? - What is wrong?
- They're pencil cases. - They are pencil cases.
- It's a tea set. - It is a tea set.
Ответ: смотри решение выше.