in Gnome there is a keyboardswitchapplet. If you click right on the panel you can add it under Utility.
But forChinese it might be more complicated. see : http://fedora.redhat.com/docs/release-notes/
This section includes information related to the support of various languages under Fedora Core.
The default Input Method (IM) for Chinese (Simplified and Traditional), Japanese, and Korean has been changed to IIIMF тАФ the Internet/Intranet Input Method Framework. IIIMF is supported as a native GTK2 IM module, and also through XIM using the httx client. IIIMF supports the use of multiple Language Engines (LEs) at the same time; using the GNOME Input Method Language Engine Tool (GIMLET тАФ an applet) it is possible to switch between LEs of different languages inside GTK2 applications.
IIIMF currently defaults to using Ctrl-Space for toggling the input method on and off (Emacs users can use Ctrl-@ instead of Ctrl-Space to set the mark.)
To switch between IIIMF and the legacy XIM input methods, use the im-switch command. Enter the following command for more information:
What is a GF? And what is IME?