药材巴豆中具有刺激性（泻下）和致癌作用的化学成分是（）
A.巴豆醇
B.巴豆苷
C.巴豆素
D.巴豆油酸
E.巴豆醇的双酯类化合物
参考答案：E
妊娠12周以内，胚胎自然殒堕者称（）
A.小产
B.胎漏
C.胞阻
D.堕胎
E.滑胎
A: What's the matter?
B: I have stomachache. Maybe I have eaten ______ tonight. [ ]
A. too much
B. too many
C. much too
D. many too
