upper wing coverts的用法和样例：
例句
- Its tail is long and black with gray uppertail coverts and orange brown undertail coverts.
尾羽修长黑色，尾上覆羽灰色，尾下覆羽橙褐色。 - Usually there is a distinct contrast between the black primaries and brown coverts, still evident at middle distances.
长尾水剃通常在黑色的初级飞羽与棕色的覆羽之间有著明显的对比，在中距离的时候仍是可见的。
