Questions & Answers about Из-за шума в вагоне я не расслышал, на какой станции нам нужно выйти.
Из-за means because of or due to. It introduces the reason something happened.
So из-за шума means because of the noise.
A very important grammar point: из-за takes the genitive case, which is why шум becomes шума.
- шум = noise
- шума = of noise / because of the noise
Because из-за always requires the genitive case.
The base form is:
- шум = noise
After из-за, it changes to:
- из-за шума = because of the noise
This is just a case requirement, not a special meaning of the noun itself.
В вагоне means in the carriage / in the train car.
- вагон = a railway carriage, train car, subway car, etc.
- в вагоне = in the carriage
Here в means in/inside, and because this is location, вагон goes into the prepositional case:
- вагон
- в вагоне
A native English speaker may want to translate вагон simply as train, but it is more specific than that: it means one carriage/car rather than the whole train.