not having the ability to do something as it should be done

an incompetent teacher/doctor 不称职的教师／医生

He has described the government as corrupt and incompetent. 他形容政府是腐败无能的。

someone who does not have the ability or skill to do something as it should be done

The country's being governed by a bunch of incompetents. 这个国家目前由一群无能之辈统治着。