paper纸，纸张，文件，没有缩写形式

例句：Denmark recycles nearly 85% of its paper.

丹麦的纸张回收率近85%。

She wrote something on a small piece of paper.

她在一小片纸上写了点什么

Sorting these papers out is going to be a long job.

整理这些文件是很费工夫的事