Just installed the surround plugin.
New buffer, type Hello World. Say I want to surround that with quotes.
In normal mode, V to get into visual mode, s to get into surround
Except it doesn't, s deletes the entire line.
The default visual mode mapping of surround.vim is Shift-S, not lowercase s.
You can check whether it's defined with :verbose vmap S. Do the other surround.vim mappings (ys, cs, ...) work? If not, check :scriptnames and :set runtimepath? for troubleshooting.
This can also be a key binding collision with the yankstack plugin. To fix it, append call yankstack#setup() to your .vimrc file. For more info, see the discussion on GitHub.
来源：https://stackoverflow.com/questions/13497990/vim-surround-not-working-for-me-s-key-deletes-instead-of-surrounds