下列属于CA认证中心功能的有()
A.证书的申请
B.证书的颁发
C.证书的查询与更新
D.证书的作废归档
参考答案:B, C, D
内服壮阳通便,外用杀虫止痒的药物是()
A.硫黄
B.雄黄
C.明矾
D.蜂房
E.硼砂
Tom never _____ fun at home. [ ]
A. have much
B. has any
C. have any
D. has many