他的解释如此清晰，连小孩子都能理解。

His explanation was remarkable for its ___lucidity, making it easy even for children to understand.

她的解释非常清晰，所有人都能理解。

Her ___lucidity made the explanation easy for everyone to understand.

湖水清澈见底，在阳光下闪耀着晶莹的光辉。

The ___lucidity of the lake water sparkled brilliantly in the sunlight.