Tom was born __ December the first.[ ]
A. in
B. on
C. at
D. during
答案:B
简述吸附速率
新生儿应接种
A.麻疹疫苗B.乙型脑炎疫苗C.脊髓灰质炎疫苗D.百、白、破混合制剂E.乙肝疫苗