She rides the bus to school every day.
I think that this sentence is ambiguous enough as to be read in different two ways; the one is that she is actually a bus driver who works for the affair, and the other is that she is not a bus driver, but a student who goes to school every day by bus. The reason why she can be a driver is that we use 'ride' in this case "A man is riding a horse." That is to say, the man is actually a driver of the horse. However, why is the sentence always read in the second way ? I don't understand why native speakers do. At least for me, there seems to be a tiny margin where it can be read in the first way.