Hello,everyone:所有答案都写在答题卡上，只交答题卡。
I．单项选择：（共10分）
( ) 1. ----How do you learn English, Toby?
---I often practice English _____ talking _____ my American friends.
A.in;to B. by; of C. by; with D. by; about
( )2.The math problem is _______ hard for me ______ work out.
A. both; and B. so; that C.enough; to D. too; to
( )3.She is a _______ girl and she always says to her teachers _______.
A polite; politely B politely; polite C.polite; polite D politely; politely
