Yeah, I've tried those and a couple others. They didn't work.
I find that if I log into my Google account at the start of each session, it resets everything to English. If I close my browser and open it again, everything is back to Chinese and I have to log into my Google account again. It's getting annoying.
EDIT: I may have found the solution. I unchecked the option to clear cookies when the browser closes. Funny, I never had this problem until a couple of days ago.