n.

1. 改进，改善；增进[U][C][（+in）]
   I cannot see any improvement in your writing.

   我看不出你在写作方面有什么改进。

2. 改进处，改善处[C]
   Painting the room yellow is a great improvement.

   把这房间漆成黄色确实好多了。

3. 改善的事物；胜过他人的人[C][（+on/over）]
   This composition is a great improvement on the one you wrote last week.

   这篇作文比你上星期写的那篇进步了许多。

n.

▸a thing that improves something or is better than something else:

home improvements.