Clean, clear, or pure in the sense of being free from dirt or impurities.
川の水が清く透明で魚が泳いでいた。
The river water was clear and pure, and fish were swimming.
いつも部屋を清く保つようにしている。
I always try to keep my room clean.
清い水で手を洗ってから作業を始めた。
I washed my hands with clean water before starting work.
Pure, innocent, or chaste; morally or emotionally untainted, often used to describe sincerity or platonic feelings.
子どもの心は清いと言われることが多い。
People often say that children's hearts are pure.
彼らは清い友情で結ばれている。
They are bound by a pure friendship.
清い愛を守るために、互いに約束した。
They promised each other to protect their pure love.