in the middle - в середине
in the centre - в центре
at the top - наверху
at the bottom - внизу
on the left side - слева
on the right side - справа
in the background - на заднем плане
in the foreground - на переднем плане
in the top left-hand corner - в левом верхнем углу
in the top right-hand corner - в правом верхнем углу
in the bottom left-hand corner - в левом нижнем углу
in the bottom right-hand corner - в правом нижнем углу

Example:

The scene takes place in the country.
In the foreground there is an apple tree.
Its curved trunk is on the left side of the picture. The branches are on the top.
An apple, surrounded by a halo, is hanging from a branch.
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