Complex sentence: Abrasion is the mechanical scraping of a rock surface by friction between rocks and moving particles during their transport by wind, glacier, waves, gravity, running water or erosionr friction, the moving particles dislodge loose and weak debris from the side of the rock.
Split into simpler sentences: Abrasion is the mechanical scraping of a rock surface by friction between rocks and moving particles during their transport by wind, glacier, waves, gravity, running water or erection. After friction, the moving particles dislodge loose and weak debris from the side of the rock.