湖中的水极其清澈。

The water in the lake is ___crystal ___clear.

浅海的清澈海水让潜水员们惊叹不已。

The ___crystal ___clear water of the shallow sea amazed the divers.

她的解释非常清晰，没有留下任何困惑的余地。

Her explanation was ___crystal ___clear, leaving no room for confusion.