水飞的目的是
A.去除杂质洁净药物
B.除去药物中可溶于水的毒性物质
C.使药物质地细腻
D.防止药物在研磨过程中粉尘飞扬
E.缓和药性
参考答案:A,B,C,D
The time is not far away _______ the news will be made known ________ will represent our company to attend the coming medical conference to be held in Beijing.
A.until; who
B.when; who
C.before; which
D.when; whenever
拉萨与北京相比,海拔高度要高出数千米,所以通常拉萨地区的大气压强______北京地区的大气压强.(选填“高于”、“等于”或“低于”)