WWB: Wind, water, birds -- stochastic natural sounds composed of lots of individual random events, all of it very healthy, all of it sound that we evolved to over the years.
风水鸟 风声 水声 鸟声 大自然的声音 它们都由各种不同的细节组成 对健康十分有好处 因为都是我们进化过程中我们陪伴我们的声音