每当我尝试执行 vim 时，终端都会显示：程序“vim”可以在以下包中找到：
* vim
* vim-gnome
* vim-tiny
* vim-athena
* vim-gtk
* vim-nox
Try: sudo apt-get install <selected package>
所以，我想大多数同学都做了，sudo apt-get update而sudo apt-get install vim却没有奏效。我输入后终端显示此消息sudo apt-get install vim
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package vim is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'vim' has …