There's an armchair ... the window.
next to
An alien is hiding ... the rock.
behind
The family is sitting ... the table.
at
A woman is standing ... the sea.
in front of
There are a lot of books ... the shelf.
on
There's a bookshelf ... two beds.
between
The kitten is sitting ... the box
in
The girl is reading ... the tree.
under
The ball is ... the box.
above