n.清潔；潔白
In open cycle condition,the frequency of the cleanness should base on cooling water quality. 在開式循環(huán)的情況下，清潔的間隔時間長短要根據(jù)冷卻水的性質(zhì)而定。
The white in the shoes symbolizes purity and cleanness. 球鞋中的白色象征著純潔和潔白。
