https://www.virtualbox.org/wiki/Linux_Downloads
1.Add the following line to your/etc/apt/sources.list:
deb http://download.virtualbox.org/virtualbox/debian xenial contrib
2.wget -q https://www.virtualbox.org/download/oracle_vbox_2016.asc -O- | sudo apt-key add -
wget -q https://www.virtualbox.org/download/oracle_vbox.asc -O- | sudo apt-key add -
3.sudo apt-get update
sudo apt-get install virtualbox-5.1
4.sudo apt-get install dkms
安装的时候可能出现依赖包，等什么的问题。就用提示的那句话解决。
安装那个扩展包，下载下来用virturalbox打开。
