产蛋下降综合症的主要传播途径是()
A.鸡虱
B.蚊子
C.空气
D.羽毛
E.经蛋传播
参考答案:E
“Mike is often absent from class.” “Tell him he _ _ answer for it if he goes on behaving like that.”
A.shall
B.will
C.would
D.can
健康小儿5个月体重约为
A.2 kg
B.4 kg
C.6 kg
D.8 kg
E.10 kg