Viking images show that the dunes are similar in size and form to sand dunes on Earth.
(Viking images; show; that the dunes are similar in size and form to sand dunes on Earth) Context(Viking images show,List([0, 18))):(the dunes; are; similar in size and form to sand dunes on Earth)
Viking images show,List([0, 18))
Viking images the dunes
show are
that the dunes are similar in size and form to sand dunes on Earth
similar in size and form to sand dunes on Earth