表面活性剂在药剂学中不能用于
A.增溶
B.防腐
C.润湿
D.乳化
参考答案：B
已知A＝{x|x＋1＞0}，B＝{－2，－1,0,1}，则(∁RA)∩B＝( )
A．{－2，－1} B．{－2} C．{－1,0,1} D．{0,1}
Not until you told me what had happened, ________. [ ]
A. didn’t I know anything about it
B. I knew nothing about it
C. did I know anything about it
D. had not I known anything about it
