Berth near the smooth surface of the lake at sunsetBerth near the smooth surface of the lake at sunset
A lonely boat on the blue surface of the sea under white cloudsA lonely boat on the blue surface of the sea under white clouds
A floating flock of dolphins above the surface of the waterA floating flock of dolphins above the surface of the water
Lighthouse surrounded by a smooth surface of waterLighthouse surrounded by a smooth surface of water
В математике: граница, отделяющая геометрическое тело от внешнего пространства. Наружная сторона чего-н..