Can't understand Kanji, so please use furigana in answers :)
Context: I'm using Rosetta stone, so there's just pictures. The picture accompanying the first sentence is a girl sleeping on a beach, the picture for the second sentence is just some random guy in mid-stride, walking on top of a mountain.
おんなのこは かいがんで ねています
おとこのひとは やまを あるいています
I'm confused about the use of で in one and the use of を in the other. As I understand it, で implies wandering around inside some fixed borders, whereas を indicates going through a location.
Would I be right in thinking the first sentence uses で to imply the girl is sleeping on the beach/within the borders of the beach, and を implies the man is walking through the mountains, not within them?