So, the expression to have ants in your pants means you cannot sit still.

所以，to have ants in your pants这个表达的意思是你不能安静地坐着。

You would also not want to have ants in your pants. That is, to be restless and unable to sit still.

你也不想have ants in your pants(坐立不安)，就是不安分坐不下来。