You must ____________ a good mountain bike.[ ]
A. had
B. have
C. has
D. having
答案:B
刺猬皮、水蛭宜采用的炮制方法是
A.土炒B.米炒C.蛤粉炒D.滑石粉炒E.砂炒
PH值是表示水的酸碱性的指标,PH↑()。
A.碱性↑
B.碱性↓
C.酸性↑
D.酸性↓