sentences: an ocean plant is a kind of water plant & if fossils of a water animal or plant are found in a place then that place used to be covered by water in the past ->  if fossils of ocean plants are found in a place then that place used to be covered by water in the past  if fossils of ocean plants are found in a place then that place used to be covered by water in the past & a desert is a kind of place & a fossil of an ocean plant is found in the desert -> the desert used to be covered by water in the past