purify /ˈpjuərifai/ vt. 使纯净，提纯，使纯洁： The salt was specially purified for use in medicine. 用于药中的盐是专门提纯过的。

 purity /ˈpjuəriti/ n. ［u］纯净，纯洁: purity of thought, word, and deed 思想，言语和行为的纯洁 No one doubts the purity of his motives. 无人怀疑他动机的纯洁性。