请用所给的代词填空。
this, that, these, it
1. _______ keys are mine. That is yours.
2. What's ________? It's an egg. What's ________ over there? It's an orange.
3. Look at ________ pencils. Are they Lucy's? No, these aren’t hers.
4. Hi, Mum, ________ is my friend, Lucy.
5. What is it? ________ is an apple.
