回复：刚拿绿卡或还没有拿到绿卡就出境了，在境外大约四年，将来对保持绿卡身份，或入籍有什么影响。

请问8、皮夹老师，加拿大公民，在美国即将上完初中高中，父母的485排期刚到，不确定今年上大学前能否拿到绿卡，所以不能申请助学金，加拿大的学费很便宜，想回加拿大上大学，研究生时再会美国读。会有什么不利吗？

-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.

一是刚拿绿卡或还没有拿到绿卡就出境了，在境外大约四年，

将来对保持绿卡身份，

-Need to have RP to stay outside US for > one year < two years. See above.

或入籍有什么影响。

-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.