无论哪种类型EIA都有：（）
A.固相抗原（抗体）
B.酶标抗体（抗原）
C.显色剂
D.终止剂
参考答案：A, B, C, D
.
It took him a few hours ________ English while I spent a few hours _____ Chinese.
A reading , to read B to read , reading C read ,read D reads ,reading
简述苦肉计
