When the glacier moves through a valley, it scrapes along the sides of the surrounding mountains, creating grooves and striations .
(it; scrapes; L:along the sides of the surrounding mountains; T:When the glacier moves through a valley) Context(it scrapes,List([41, 51))):(it; scrapes creating; grooves and striations)
it scrapes,List([41, 51))
it it
scrapes scrapes creating
L:along the sides of the surrounding mountains T:When the glacier moves through a valley
grooves and striations