An alien is hiding ... the rock.
behind
He is ... the box..
in
He is ... the roof
on
There's a bookcase ... two beds.
between
There's a tree ... the house.
in front of
Throw the litter ... the rubbish bin.
in
There's a wooden house ... the trees.
between / next to
There are presents ... the tree.
under
She is sitting ... a rock.
on
The cat is ... the bed.
under
There are a lot of books ... the shelf.
on
The girl is reading ... the tree.
under
The kitten is sitting ... the box
in
He is ... the car.
in
Let's relax ... the fireplace.
next to / in front of
There are nice flowers ... the table
on
A woman is standing ... the sea.
in front of
She is sitting ... a rock.
on
The dog is ... the table.
under
A tiger is ... a cat.
next to
There's an armchair ... the window.
next to