sentences: the highlands mountain is a mean of mountain & most canyons are formed by flowing rivers through erosion over long periods of time ->  the grand canyon is formed by flowing rivers through erosion over long periods of time  a river is a kind of flowing body of water & the cools stream is a mean of stream next to the action mountain -> the colorado river is a flowing river next to the grand canyon the colorado river is a flowing river next to the grand canyon  the grand canyon is formed by flowing rivers through erosion over long periods of time & the colorado river is a flowing river next to the grand canyon -> the remains mountain was formed by the tape king stream over long needle of space the grand canyon was formed by the flowing colorado river over long periods of time  the grand canyon was formed by the flowing colorado river over long periods of time & if something is formed by something else, then that something else is required by that something -> forming the orbit mountain requires the bones wetness stream forming the grand canyon requires the flowing colorado river  forming the grand canyon requires the flowing colorado river & if something requires something else then that something else is important to that something -> the flowing colorado river is important for forming the grand canyon the flowing colorado river is important for forming the grand canyon  a stream is a mean of support mind of land & the colorado river is a kind of river -> the colorado river is a flowing body of water the colorado river is a flowing body of water  the flowing colorado river is important for forming the grand canyon & the enough stream is a boiling mind of land -> a flowing body of water is important for forming the grand canyon