操作示范教学的特点是（）。
A、施教复杂，但便于掌握
B、施教复杂，不便于掌握
C、简便易行，便于掌握
D、只练不讲，不便于掌握
参考答案：C
My friend with my host family in the USA as an exchange student led me into a world where
I would not have enjoyed American culture so much.[ ]
A. meanwhile
B. nevertheless
C. therefore
D. otherwise
It is illegal for a public official to ask people for gifts or money ________ favors to them. [ ]
A．in preference to
B．in place of
C．in agreement with
D．in exchange for
