1.备份软件源列表文件
sudo cp /etc/apt/sources.list /etc/apt/sources.list_backup
2.编辑软件源配置文件（几种方法任选一）
gedit /etc/apt/sources.list（gnome）
kate /etc/apt/sources.list（KDE环境）
mousepad /etc/apt/sources.list（X环境）
3.替换文件中所有内容，保存文件，网易的软件源
deb http://mirrors.163.com/ubuntu/ intrepid main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ intrepid-security main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ intrepid-updates main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ intrepid-proposed main restricted universe multiverse
deb http://mirrors.163.com/ubuntu/ intrepid-backports main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ intrepid main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ intrepid-security main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ intrepid-updates main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ intrepid-proposed main restricted universe multiverse
deb-src http://mirrors.163.com/ubuntu/ intrepid-backports main restricted universe multiverse
4.更新软件源
sudo apt-get update
5.还原备份
sudo cp /etc/apt/sources.list_backup /etc/apt/sources.list