Log out of your computer and create a new user account which has limited rights to change the PC's Settings.

退出电脑帐户，新建一个改变设置权限较低用户帐户。

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In terms of security, delegates can only view your inbox and respond to messages on your behalf; they can't access gChat, change your password, or fiddle with other account settings.

考虑到安全因素，邮件代理只允许你查看收件箱和以你自己的账户回复邮件，而不允许访问到gChat服务，修改用户密码或者修改账户的其他设置。

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It is possible to change sound Settings on Account screen.

它有可能改变帐户屏幕上的声音设置。

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Go into the account settings and change the signature on his emails.

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