为了保证系统的安全,现在的LINUX系统一般将/etc/passwd密码文件加密后,保存在( )文件
A. /etc/password
B. /etc/shadow
C. /etc/group
D. /etc/libasafe.notify
添加一个用户，起初指定他的帐号在30天后过期，现在想改变这个过期时间，用______命令最合适。
A. usermod －a
B. usermod －d
C. usermod －x
D. usermod －e
修改用户的个人说明，应使用命令______
A. groupmod-c"Thisisatest" user1
B. chmod-c"Thisisatest" user1
C. usermod-c"Thisisatest" user1
D. usermod-e"Thisisatest" user1
The young woman seated next to us at the restaurant had an exotic air, her looks and style, we thought, made it likely that she was not American born.
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