1. 释义：if a situation goes downhill, it gets worse
2. 理解：downhill作为形容词是uphill相对应的反义词，downhill作为副词则更常见更好用，一般与go连用，意思是“每况愈下的”，当我们想表达某件事情变得越来越糟时，除了说get/become worse, worsen, deteriorate, go from bad to worse之外，还可以用go/slide/head downhill 来替代。
3. 应用：
1）翻译：情况正在每况愈下，我们不得不做点什么了。
Things are going downhill. we have to do something about it.
2) 造句：
The economy of the physical stores has headed downhill with the rising of the online economic in recent years.(随着近年来网络经济的崛起，实体店经济形势每况愈下。）
