主要Ig的特性和功能中，"血清Ig升高说明有近期感染"属于（）
A.IgG
B.IgM
C.IgA
D.IgD
E.IgE
参考答案：B
pKa是指
A．药物90%解离时溶液的pH值B．药物99%解离时溶液的pH值C．药物50%解离时溶液的pH值D．药物全部解离时溶液的pH值E．药物不解离时溶液的pH值
— Mr. Wang, whom would you rather ____ the important meeting?
— Tom. [ ]
A. have attend
B. have attended
C. having attend
D. have to attend
