be short of：缺少;短缺;缺乏;

be short for：是…的简称；是…的缩写

例句：

“CEO” is short for “Chief Executive Officer.”

Otherwise you’ll be short of money all term.否则你整个一学期都将缺钱。

The rebels were short of gunpowder.反叛者们缺少弹药。