Learn Polish: Stary samochód jedzie wolno. - The old car is driving slowly.

Jedzie comes from the verb jechać, which means to go by a vehicle (driving, riding, sailing). Idzie (from iść) means to go on foot. Since a car (samochód) is a vehicle, it jedzie (is driving), not idzie (is walking).

Does jedzie mean "drives" or "is driving"?

Polish doesn't have a separate "-ing" tense like English. However, because jechać is a unidirectional verb (meaning it describes movement in one specific direction at a specific time), jedzie almost always means "is driving" right now. If we wanted to say the car drives slowly in general or habitually, we would use its multidirectional pair, jeździć.

Why is the adjective stary and not stara?

Adjectives must match the gender of the noun they describe. Samochód (car) is a masculine noun, so it takes the masculine adjective ending -y to become stary. If we were talking about a feminine noun, we would use stara.

I've seen wolno used to mean "allowed". Does it mean "slowly" here?