debris是不可数名词,没有复数

debris

n.残骸;碎片;破片;残渣;垃圾;废弃物

例句：

Falling debris rained on us from above.

碎片从上面像雨点儿一样落在我们身上。

A number of people were killed by flying debris.

有数人被飞射的碎片击中身亡。

Clear away leaves and other garden debris from the pond.

把池塘里的树叶和其他庭园垃圾清除干净。

The roof collapsed, showering us with dust and debris.

屋顶塌了下来，灰尘、碎片纷纷落在我们身上。