— Are you okay? — I have a .[ ]
A. head
B. stomachache
C. book
答案：B
Electricity plays _____ part in our life that it is unimaginable to live without it. [ ]
A. such important
B. so important
C. such important a
D. so important a
利用浓缩原理、分子筛和电荷原理分离蛋白质的技术，称作
A．等电聚焦
B．醋酸纤维薄膜电泳
C．不连续的聚丙烯酰胺凝胶电泳
D．琼脂糖电泳
