green card holder, plan to use Canadian passport travel to EU, when back to US:
1. need to have green card with a valid passport? Not only green card?
2. any problems of dual nationalities? Before only used chinese passport to China, Canadian passport never has been used. So record in US is chinese citizen with US green card.
3.In general, is it always feasible to use chinese passport back to China, while use Canadian one traveling to countries where PRC are required to apply visas?
Thanks a lot!