Ⅰ. 单项选择。（15分）
21. I like learning English ____ speaking it with my friends.
A. for B. by C. through D. in
22. This is ____ for the table.
A. a clothes B. a cloth C. clothes D. cloth
23. My parents go to work by bike ____ by bus.
A. instead B. instead of C. but D. and
