II. Multiple choice（本题共15分，每小题1分）
Choose the best answer from A、B or C according to the meaning of the sentence.
( )21. There is big supermarket in center of our city.
A. a; the B. the; a C. the; the
( )22. All the visitors live on floor.
A. two B. second C. the second
( )23. This is my twin sister, Lucy. Not only she but also I good at drawing.
A. is B. am C. are
