功能清热化痰，润肠通便的药物是（）
A.瓜蒌
B.川贝母
C.礞石
D.马兜铃
E.枇杷叶
参考答案：A
It was very _____ him to make room for an old person. [ ]
A. polite for
B. polite of
C. polite to
D. polite in
存储-转发方式有两种：一是报文交换，二是（）。
