--- a/.vimrc	Fri May 08 15:20:26 2015 +0800
+++ b/.vimrc	Wed May 13 15:40:20 2015 +0800
@@ -35,7 +35,7 @@
 set shiftround
 set expandtab
 
-set listchars=tab:>-,trail:·
+set listchars=tab:>-,trail:·,nbsp:⍽
 
 set number        " show line numbers
 set laststatus=2  " always show status line