Something I did caused this same behavior. In my case, I think I did it to myself because I was actually doing things to the language and keyboard settings. Fortunately, the menu items seem to come up in a combination of English and Chinese, so I was able to find the tool I needed. First, read this:
Install/Remove Language show only English, no other choice
Note the positions of the controls in the dialog. They will be labeled in whatever language you have set, but they will be in the same place. You have to drag "English" or any other language you want to the top of the list. Then click the "Apply System-Wide" button. You will be prompted for your password.
What I can't figure out is why I had Chinese localizations installed in the first place.