Translation:Nine buses and four cars turn onto our street.
There's this consistent idiosyncrasy in the English translations, which is to refer to things in the street. The problem is, this is kind of English's fault, since it's really inconsistent about when it says "in the street" vs. "on the street". As a general rule, though:
on the surface of the street - on the street
within a zone consisting of the surface of the street and anything on or above the pavement that could conceivably be hit by an oncoming car - in the street
inside of the pavement itself - in the street (I'm not sure I've ever heard this used, but still)
of a building or pedestrian, right next to the street - on the street
Naturally, there's quite a bit of overlap between the first two. Basically, you'd use in the street when the context revolves around someone or something getting smashed into because of it's being in the way of a car, e.g. mothers often tell their children not to play in the street, not on the street - not because they're particularly worried about how horrifyingly dangerous asphalt is, or something, but because they're worried about their children being hit by a car.
This certainly a pretty arbitrary distinction, but one that this course consistently fails to make. In English, I don't live in XYZ street, I live on XYZ street, because my house is neither right in the path of a car (driven by a sober driver) nor inside the pavement of the road.
And this is all the more problematic in this sentence because "turn into" is a phrasal verb in English that means "to become" or "to be transformed into".
TL;DR unless a bunch of buses and cars are literally being transformed into a road, we should say that they're turning onto our street. :)
I think it is easier to see with road. To continue what you are saying, for a thing that is in or on the road:
It is in the road if the thing should not be there:
- The boys are playing in this road (and may be hit by cars)
- I am walking in that road (in the middle, where cars go)
- The fallen tree is in that road (and a car hit it)
- The car is parked in the road (and blocking cars)
It is on the road if it is OK being there.
- The boys are playing on this road (on the sidewalk there)
- I am walking on that road (instead of driving)
- The fallen tree is on that road (in his garden)
- The car is parked on the road (instead of the parking lot)
The same is true for street, except that a street sometimes has less cars, so it's OK sometimes: the boys play soccer in the street (and move when a car comes through)