1.This is____eraser and that is____ruler.
2.        book is____English book.
3. Is this her ____ baseball?
4. —What color is ____ schoolbag?
    —It's yellow.
5. Mike is at____school.
6. ____orange is____orange.
7. Is that your____notebook in____ lost and found case?
8. —What's this?
    —It's____ID card.
9. —Is that____watch?
    —No,it isn't. It's____set of keys.
10. ____ baseball is white.

A.a, a        
B.an, an        
C.a, an        
D.an, a

[     ]

A. a, a
B. an, an
C. a, an
D. an, a