多数情况用作不可数名词，但当表示具体的特别是多项不同的发展则也可用为可数复数。

例句：It is the end product of exhaustive research and development.

这是经过充分研究和开发的最终产品。

扩展资料

This land is ripe for development.

这片土地适宜开发。

He bought the land for development.

他买了这块地准备开发。

A vast tract of land is ready for development.

一大片土地正待开发。

Development of the area would endanger wildlife.

开发这一地区将会危及野生生物。

The town centre was zoned for office development.

镇中心被划定为写字楼开发区。

They had laid the groundwork for future development.

他们为此后的发展奠定了基础。