①名词为purity
n. 洁净,纯净纯洁,清白(声音、文章、音乐等的)清晰
②动词为purify
v. 使(某物)洁净,净化变纯净洗涤(思想),净化(心灵)提纯,精炼
It can also help to purify the water quality, reduce pollution and improve environment.
荷花还可净化水质、减少污染、改善环境。