add key

wget -q https://www.virtualBox.org/download/oracle_vBox_2016.asc -O- | sudo apt-key add -

add sources

sudo sh -c 'echo "deb [arch=amd64] http://download.virtualBox.org/virtualBox/debian xenial contrib" >> /etc/apt/sources.list.d/virtualBox.list'

update

apt update

install

apt install virtualBox-5.1

add extension pack

  download

wget -O ~/Downloads/Oracle_VM_VirtualBox_Extension_Pack-5.1.22-115126.vBox-extpack http://download.virtualBox.org/virtualBox/5.1.22/Oracle_VM_VirtualBox_Extension_Pack-5.1.22-115126.vBox-extpack

   在下载下来的文件上单击鼠标右键，用virtualBox打开即可启动扩展包的安装程序。