To covet something without taking practical steps to achieve it; it implies that merely wishing for something is ineffective, and one should instead take practical action.
小明总是梦想着成为一名优秀的程序员，却从不学习编程知识。这不就是临渊羡鱼吗？
Xiao Ming always dreams of becoming an excellent programmer, but he never bothers to learn any programming skills. Isn't that like standing by the deep pool and envying the fish?
Next Idiom