Night lights of the metropolis on the background of the water surfaceNight lights of the metropolis on the background of the water surface
Cumulus sunset clouds over the surface of the lakeCumulus sunset clouds over the surface of the lake
The red bridge over the water surface goes into the fogThe red bridge over the water surface goes into the fog
В математике: граница, отделяющая геометрическое тело от внешнего пространства. Наружная сторона чего-н..