Translation:When I was in that country, I used to see many cars.
I was marked wrong for saying, "When I used to go to that country, I would see many cars." I think my answer makes more sense. The auxiliary "used to" implies that the activity or situation has stopped and no longer occurs. The sense of my answer is that I went to that country several times in the past but now I no longer go there; when I was there (in the past), there were a lot of cars.
The DL answer would have it that, I went to that country in the past and may still go there - or not - and there used to be a lot of cars there, but there no longer are many cars there at all. The cars disappeared for some unknown reason. That's pretty strange.
As in English there is one word for 'automobiles' and another for 'cars' in Italian. If automobili is given in the sentence why would you want to write cars except to save yourself the extra effort of writing automobiles? Then you lose a heart and then you spend time complaining about it. Keep it simple. : )