請問8、皮夾老師，加拿大公民，在美國即將上完初中高中，父母的485排期剛到，不確定今年上大學前能否拿到綠卡，所以不能申請助學金，加拿大的學費很便宜，想回加拿大上大學，研究生時再會美國讀。會有什麽不利嗎？
-Fine but the child needs to have reentry permit (RP) to stay in Canada and RP can allows him/her stay in Canada for less than two years, but he/she may renew the RP for another term of <2 years before it expires.
一是剛拿綠卡或還沒有拿到綠卡就出境了，在境外大約四年，
將來對保持綠卡身份，
-Need to have RP to stay outside US for > one year < two years. See above.
或入籍有什麽影響。
-It will delay for 入籍 because US citizenship application require physical presence in US for at least 30 months in 5 years and not stay outside US for > 6 months continuously.
