间接凝集试验常用的载体()
A.人O型红细胞
B.活性炭
C.明胶颗粒
D.聚苯乙烯胶乳
E.皂土
参考答案：A, B, C, D
—I think students should be allowed to do homework with friends.
—_______. They talk instead of doing homework. [ ]
A. I agree
B. I disagree
C. I'm afraid so
D. I hope so
危险程度与什么因素有关？
