I. 单项选择。(每小题1分,共10分)
( ) 21. Mary is twelve years old ________ she’s a student.
A. but B. and C. or
( ) 22. — _______________________?
— My name’s Tom.
A. How old are you
B. Where are you from
C. What’s your name
( ) 23. — Are they in Class 2?
— ______________. I am in Class 2, too.
A. Yes, they are
B. No, he isn’t
C. No, they aren’t