—Is that ______ volleyball?—Yes. Bill likes playing ______ volleyball. ______ volleyball is his.

It’s ___________ black．It’s ________ black ruler．

This is an             .  

There is ______ English book on the teacher’s desk.

---Look! There is         beautiful rainbow in the sky．
---Wow, it’s so beautiful. I’d like to take a photo of     rainbow before it disappears．

Simon likes playing ______ football but Sandy likes playing ______ piano.

—Have you seen         book on the desk?
—Is it         English book? I saw it just now.

This is ________ apple. It’s ________ green apple.
A. a, an               B. an, a               C. an, an