1. be short of sth 缺少某物，同义词是lack sth。如the boy is short of courage.这个男孩缺少勇气。

2. be short for sth. 简称，缩写。如 USA is short for United States of America. USA是United States of America的简称。

3. for short. 简称，缩写。My name is Econ Zhao, Econ for short.

4. be short with.粗暴无礼的,简慢的;暴躁的。 例如：He was short with me this morning. 他今天早上对我无礼。