更换国内源
可以在阿里官网镜像查找对应系统，点击帮助找到更换方法
更换Ubuntu16.04
备份
sudo cp /etc/apt/sources.list /etc/apt/sources_init.list
修改
sudo gedit /etc/apt/sources.list
替换为
deb http://mirrors.aliyun.com/ubuntu/ xenial main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial main
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main
deb http://mirrors.aliyun.com/ubuntu/ xenial universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
deb http://mirrors.aliyun.com/ubuntu/ xenial-security main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main
deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security universe
更新
sudo apt-get update
修复损坏的软件包，尝试卸载出错的包，重新安装正确版本的
sudo apt-get -f install
升级软件
sudo apt-get upgrade