描述药物对机体的作用特征（）
A.消除
B.药效学
C.药动学
D.首关效应
E.零级消除动力学
参考答案：B
— Do you know _________? —No, I don’t know.
A．where he’s from
B．where is he come
C．where does he come from
D．where comes he from
