父母在美等绿卡，又收到Ref。要证明自已是否是共产党员及其活动。这个证明和公证哪里办理？父母从来不是党员，485申请也选的No，不知为什么会收到这种Ref。先谢了！
-They just write (by using Chinese) a statement addessign that they never joined the Chinese Communist Party, resepetively, and then, you ask one friend of yours to translate it into English following the USCIS requirements. Don't need to 公证.
See this link for the translation requirements:
https://www.immihelp.com/translation-of-non-english-documents-for-us-immigration/
