乙脑的传染源主要是（）.
A.患者
B.带毒者
C.幼猪
D.牛
参考答案：C
—Boys, would you mind not playing basketball here?
—_____, Mr. Li. [ ]
A. No, thanks
B. Sorry, we won't do it again
C. You are welcome
D. I can't stand it
按出疹时间排序，出现皮疹最晚的是（）
A.水痘
B.天花
C.麻疹
D.猩红热
E.传染性单核细胞增多症
