They added that no Earth-like features, such as mountain chains, great valleys, ocean basins, or continental plates, were identifiable in 
(They; added; that no Earth-like features, such as mountain chains, great valleys, ocean basins, or continental plates, were identifiable in) Context(They added,List([0, 10))):(no Earth-like features, such as mountain chains, great valleys, ocean basins, or continental plates; were; identifiable; L:in)
They added,List([0, 10))
They no Earth-like features, such as mountain chains, great valleys, ocean basins, or continental plates
added were
that no Earth-like features, such as mountain chains, great valleys, ocean basins, or continental plates, were identifiable in
identifiable L:in