I don`t know is it available English app in App Manager, but think you should search for it. Try to find app with English language - American, UK, or else. The other way is to reflash your device with flasher 3,5. But you will loose your all apps, settings, etc. You can make a back up, but i don`t know will this back up will restore everything to CN. At least you will have a possibility to change after to English. regards.