sentences: survival to middle light and young limited / leaves sedimentary / igneous stone into metamorphic stone
docs: gneiss is metamorphic_rock. igneous_rock is stone. slate is metamorphic_rock. groundmass is igneous_rock. amphibolite is metamorphic_rock. slate is sedimentary_rock. metamorphic_rock is rock. marlite is metamorphic_rock. metamorphic_rock is stone. sedimentary_rock is stone.