improve变名词

名词形式为improvement，例如：

1.We expect to see further improvement over the coming year.我们期望来年会有更进一步的改善。

2.Is this situation not susceptible of improvement by legislation?这种状况有无可能通过立法加以改善？

3.There is still room for improvement in your work.你的工作尚有改进的余地。