俺的理解是不必是美國公民，看這裏說明，

來源: 水中撈月於 2014-09-15 12:09:17 [博客] [舊帖] [給我悄悄話] 本文已被閱讀：次

WENXUECITY.COM does not represent or guarantee the truthfulness, accuracy, or reliability of any of communications posted by other users.