Means of transport take 'de': 'de carro', 'de avião', but 'a pé'
To say how you get somewhere in Portuguese, put de in front of the vehicle and leave out the article: de carro (by car), de avião (by plane), de bicicleta (by bike), de ônibus or de autocarro (by bus). The big exception is walking. That is a pé (on foot), and riding a horse follows the same pattern: a cavalo.
English speakers trip over this for two reasons. English uses by, which tempts learners to reach for por (por carro is wrong). English also says on foot, which suggests em pé. But em pé means something else entirely: standing up.
Word list
autocarromA1busPT: de autocarro = by busaviãomA1airplanede avião = by airplanebicicletafA1bicyclede bicicleta = by bicyclecarromA1carde carro = by carcavalomA1horsea cavalo = on horsebackcomboiomA1trainPT: de comboio = by trainir a péA1to walkir a pé = to walkônibusmA1busBR: de ônibus = by buspémA1foota pé = on foottremmA1trainBR: de trem = by trainambulânciafA2ambulancede ambulância = by ambulanceandar de bicicletaA2to cycleandar de bicicleta = to cycleautomóvelmA2carde automóvel = by carbarcomA2boatde barco = by boatbondemA2tramBR: de bonde = by tramcamiãomA2truckPT: de camião = by truckcaminhãomA2truckBR: de caminhão = by truckelétricomA2tramPT: de elétrico = by tramelevadormA2elevatorde elevador = by elevatormetrômA2subwayBR: de metrô = by subwaymetromA2subwayPT: de metro = by subwaymotafA2motorcyclePT: de mota = by motorcyclemotofA2motorcyclede moto = by motorcyclemotocicletafA2motorcyclede motocicleta = by motorcyclenaviomA2shipde navio = by shiptáximA2taxide táxi = by taxitransporte públicomA2public transportde transporte público = by public transportbalsafB1ferryBR: de balsa = by ferrybotemB1boatde bote = by boatcaminhonetefB1pickup truckBR: de caminhonete = by pickup truckcarrinhafB1vanPT: de carrinha = by vancarrinha de caixa abertafB1pickup truckPT: de carrinha de caixa aberta = by pickup truckespaçonavefB1spaceshipBR: de espaçonave = by spaceshipferrymB1ferryPT: de ferry = by ferryfurgãomB1vande furgão = by vannave espacialfB1spaceshipde nave espacial = by spaceshippicapefB1pickup truckBR: de picape = by pickup trucksubmarinomB1submarinede submarino = by submarinetransporte coletivomB1public transportBR: de transporte coletivo = by public transportvanfB1vanBR: de van = by vanandar a cavaloB2to ride a horseandar a cavalo = to ride a horseastronavefB2spaceshipde astronave = by spaceshipcaiaquemB2kayakde caiaque = by kayakcargueiromB2cargo shipde cargueiro = by cargo shiphelicópteromB2helicopterde helicóptero = by helicopteriatemB2yachtde iate = by yachtlimusinafB2limousinePT: de limusina = by limousinelimusinefB2limousinede limusine = by limousinemontar a cavaloB2to ride a horsemontar a cavalo = to ride a horsemotociclomB2motorcyclePT: de motociclo = by motorcyclenavio de cargamB2cargo shipde navio de carga = by cargo shippick-upfB2pickup truckde pick-up = by pickup truckbarco a vapormC1steamshipde barco a vapor = by steamshipcanoafC1canoede canoa = by canoecarruagemfC1carriagede carruagem = by carriageesqueitemC1skateboardBR: de esqueite = by skateboardjangadafC1raftBR: de jangada = by raftnavio a vapormC1steamshipde navio a vapor = by steamshipskatemC1skateboardde skate = by skateboardtanquemC1tankde tanque = by tanktrenómC1sledde trenó = by sledcarro de combatemC2tankde carro de combate = by tankdisco voadormC2flying saucerde disco voador = by flying saucertratormC2tractorde trator = by tractorviaturafC2patrol carde viatura = by patrol car
How it works
The pattern is simply verb + de + vehicle, with no o, a, um or uma. It works with any verb of movement: ir, vir, voltar, viajar, chegar. The vehicle stays in the singular and never takes an article, even when it is feminine: de bicicleta, de moto.
Rule of thumb: if the English sentence says by + vehicle, Portuguese says de + vehicle.
Vou para o trabalho de metrô, mas volto a pé.
(I go to work by subway, but I walk back.)
Eles viajaram de avião.
(They traveled by plane.)
The words
Several vehicles have one word in Brazil and another in Portugal. The construction is identical in both countries.
Cars and road vehicles: carro, automóvel, táxi, caminhão (BR) / camião (PT), van (BR) / carrinha (PT), furgão
Public transport: ônibus (BR) / autocarro (PT), trem (BR) / comboio (PT), metrô (BR) / metro (PT), bonde (BR) / elétrico (PT), and the general transporte público or transporte coletivo
Two wheels: bicicleta, moto, motocicleta, mota (PT), motociclo (PT)
Em Lisboa, ela vai sempre de comboio para o trabalho.
(In Lisbon, she always goes to work by train.)
Fomos de táxi para o aeroporto.
(We went to the airport by taxi.)
O meu irmão vai de moto para a faculdade.
(My brother goes to university by motorbike.)
Atravessamos o rio de balsa.
(We crossed the river by ferry.)
The verb andar (to ride, to travel around) uses the same de. So andar de bicicleta means to ride a bike, and andar de carro means to ride in a car.
Aos domingos, ando de bicicleta no parque.
(On Sundays, I ride my bike in the park.)
Watch out
Walking and horses take a
You go a pé (on foot) and ride a cavalo (on horseback). Never say de pé. The fixed expressions are ir a pé (to walk somewhere), andar a cavalo and montar a cavalo (to ride a horse).
A escola é perto, por isso vamos a pé.
(The school is close, so we walk.)
A minha filha aprendeu a andar a cavalo.
(My daughter learned to ride a horse.)
Em pé means standing
It describes your posture, not how you travel.
O ônibus estava cheio e fiquei em pé.
(The bus was full and I had to stand.)
A particular vehicle takes em + article
De + noun without an article names the type of transport. When you mean one specific vehicle, usually someone's car or a certain bus, use em + article: no, na, num.
Fui no carro da minha irmã.
(I went in my sister's car.)
No por
Por carro and por avião are the classic English-speaker mistake. Use de.
Summary
For how you travel, use de + vehicle with no article: de carro, de trem, de comboio, de avião, de bicicleta. The exceptions are a pé (on foot) and a cavalo (on horseback). Keep em pé for standing, and use no or na only when you mean one particular vehicle, such as no carro do João.