请教有为父母申请绿卡经验的朋友，I-485的 part 5 都选的那一项：
1，I can read and understand English,and I have read and understand each and every question and instruction on this form,as well as my answer to each question.
2.Each and every question and instruction on this form,as well as my answer to each question,has been read to me in ____________ language, a language in which I am fluent,by the person named in Interpreter's Statement and Signature......
父母懂一点英语但没到能读懂I-485的份上。如果选我自己做翻译，需要任何文件证明吗？
先谢谢热心人的帮助！