My face book is in Chinese how do I change back to English ?

Facebook is available in 70 languages.
The language settings can be easily changed a few clicks and your whole page will be displayed in the selected language.
This can make changing it back difficult at first glance.
If you've inadvertently switched languages, going back to English is easy if you know where to look.
Log in to your account and follow a few simple steps that work regardless of the language you've changed to.

Visit facebook.com on your PC language settings are not available on the mobile site.
Enter your email address and password into the fields at the top of the page, then click the "Log In" button.
Scroll to the very bottom of the page.
You will see the word "Facebook" followed by a copyright logo.
Your current language is displayed next to the copyright symbol.
Click on the language a popup window appears, displaying all the available languages.
Click "English," then select your desired version of English.

http://romcartridge.blogspot.com/2010/05/how-to-change-language-back-to-english.html