还是可以等到我老公拿到绿卡后再申请?
-This is also OK. See above answer.
他们能否拿到绿卡后继续在加拿大完成大学学业?
-Yes, but they may need to get the reentry permit (RP) to stay in Canada if they need more time to study in Canada (RP can allow them to stay in Canada for > 1 year < 2 years).
2. 我因有特殊情况想等几年后拿绿卡,如我想要作为老公的dependent来申请,可以最迟隔多久申请?
-You can file I-485 any time if you are phyically present in US.
有没有时间限制?
-No.
除了结婚公证,孩子们的出生公证,填写485,还需要准备其它材料吗?
-See