yum grouplist
列出centos安装时的软件分组，其中Available Groups代表未安装的分组：
Available Groups:
   Tomboy
   Cluster Storage
   Office/Productivity
   Engineering and Scientific
   Beagle
   GNOME Software Development
   X Software Development
   Virtualization
   Legacy Network Server
   DNS Name Server
   GNOME Desktop Environment
   XFCE-4.4
   Base
   FTP Server
   Mono
   Games and Entertainment
   Clustering
   Java
   Java Development
   OpenFabrics Enterprise Distribution
   Emacs
   X Window System
   Graphics
   Web Server
   Ruby
   Windows File Server
   Printing Support
   KDE Software Development
   KDE (K Desktop Environment)
   Horde
   Sound and Video
   PostgreSQL Database
   News Server
   Development Tools
   FreeNX and NX
   Graphical Internet
Done

发现有xfce分组，于是
yum groupinstall "XFCE-4.4"
大功告成