"Do you want to go on an airplane or on a boat?"
Translation:Você quer ir de avião ou de barco?
I don't get it: "Você quer ir em um avião ou num barco?" Why is "em um" only contracted in the second case? o.O
Is "Vc quer andar de avião ou de barco" wrong? I read it in my manual on Portuguese as the way to say "to go by smth.(train, plane, ship etc.)"!
As a question, andar de barco/avião seems to be an invitation for a leisure trip, usually to discover it for the first time. Ir de barco/avião is asking by what means of transportation you want to travel.