既能化瘀止血，又能活血定痛的药物是（）
A.仙鹤草
B.白及
C.三七
D.大蓟
E.槐角
参考答案：C
—In the United States, what should people do when they meet someone for the first time?
—They should _____. [ ]
A. bow
B. shake hands
C. kiss
D. touch noses
