sudo cp /etc/apt/sources.list /etc/apt/sources.list_bak #備份 sudo vi /etc/apt/sources.list
/etc/apt/sources.list 文件內容
# # deb cdrom:[Debian GNU/Linux 7 _Wheezy_ - Official Snapshot i386 LIVE/INSTALL Binary 20150114-04:45]/ wheezy main deb cdrom:[Debian GNU/Linux 7 _Wheezy_ - Official Snapshot i386 LIVE/INSTALL Binary 20150114-04:45]/ wheezy main deb http://mirrors.163.com/debian/ wheezy main deb-src http://mirrors.163.com/debian/ wheezy main deb http://security.debian.org/ wheezy/updates main deb-src http://security.debian.org/ wheezy/updates main # wheezy-updates, previously known as ‘volatile‘ deb http://http.debian.net/debian/ wheezy main contrib non-free deb http://mirrors.163.com/debian/ wheezy-updates main deb-src http://mirrors.163.com/debian/ wheezy-updates main # Debian 7 "Wheezy" deb http://http.debian.net/debian/ wheezy main contrib non-free # for Youdao 字典 deb http://ppa.launchpad.net/justzx2011/openyoudao-v0.4/ubuntu trusty main deb-src http://ppa.launchpad.net/justzx2011/openyoudao-v0.4/ubuntu trusty main
原文：http://www.cnblogs.com/YoungGu/p/5186049.html