酶免疫方法测定细胞表面粘附分子的缺点是（）

A.由于内源性酶的干扰和固定剂的使用所致的非特异性显色的增加

B.特异性差

C.测定灵敏度差

D.测定不够简单方便

E.以上均是

句型转换（每空0.5分，计6分）

小题1: He went to bed after he finished his homework.     (写出同义句)

He______________ go to bed______________ he finished his homework.

小题2:The coat is so small that he can’t put on.     (写出同义句)

The coat is _____________ small for him ____________ put on.

小题3:Tom writes better than Peter.    (写出同义句)

Peter ____________ write _____________well as Tom.

小题4:. Maria doesn’t know which coat she should choose. (写出同义句)

Maria doesn’t know which coat ____________  ____________.

小题5: He didn’t pass the exam because he got a bad headache.  (划线提问)

______________  _____________ he pass the exam?

小题6: It’s about half an hour on foot from school to my home.   (划线提问)

____________  ____________ is it from school to your home?