The shape depends mainly on the temperature and water levels in the air.

VOA: special.2010.01.05

They were placed one on top of another in a circular shape.

VOA: special.2011.05.18

One of the hands keeps a flat hand shape and it just kind of lightly moves back and forth as if it were a flickering image on a screen."

VOA: special.2011.04.13

In that case, the shape of Britain's future government will depend on coalitions.

VOA: standard.2010.05.05