呈橘瓣状，背面有一条浅纵沟的药材是（）
A.蛇床子
B.砂仁
C.薏苡仁
D.牵牛子
E.地肤子
参考答案：D
It is not rare in ________ that people in ________ fifties are going to university for further education.[ ]
A. 90s; the
B. the 90s; /
C. 90s; their
D. the 90s; their
客流的主要组成要素是（）、（）和（）。
