下列与表面活性剂特性无关的是
A．适宜的粘稠度
B．克氏点和昙点
C．亲水亲油平衡值
D．临界胶囊浓度
E．表面活性
参考答案：A
I think ________ good knowledge of English is ________ great help when you are traveling around the world.
A．不填;a
B．a; a
C．a; the
D．a; 不填
It suddenly occurred to him ________ he had left his keys in the office.(2012·江西)
A．whether
B．where
C．which
D．that
