This is covered by:
AQA 8035, Cambridge IGCSE, CEA, Edexcel A, Edexcel B, Eduqas A, OCR A, OCR B, WJEC
Abrasion occurs when particles of rock and sand grind down larger rocks and cliffs. They act like sandpaper rubbing at the surface, removing tiny amounts but, as wave after wave hits the cliff base, throwing more and more sand at it, the abrasion becomes more pronounced. Think of abrasion as tiny bits of rock in the water scraping against rocks and grinding off small particles of rock.