hi, I plan to vist friends in Canada. When I return to US, what documents do I need? Will they examine my I20? Or just I-94?
Because I don't need to apply new visa if I return US within 30 days, can I go back to china and return to canada then back to US?
I mean US -> Canada -> China -> Canada -> US.
Theoritically, if all the trips are done in 30 days, it'd be ok?
Hope you guys can help. If this is doable, we chinese F1 students can have a easy way to visit home town and back to US.