与人结肠黏膜具有共同抗原()
A.大肠杆菌O14
B.溶血性链球菌
C.变形杆菌OX19
D.大肠杆菌O86
E.肺炎球菌14型
参考答案:A
— I'm sorry I _____ my exercise book at home.
— Don't forget _____ it to school tomorrow, please. [ ]
A. forgot, to take
B. left, to bring
C. forgot, to bring
D. left, to take
在因特网中,屏蔽各个物理网络细节和差异的是______。
A.主机-网络层
B.互联层
C.传输层
D.应用层