improper /ɪmˈprɑːpɚ/ adjective Learner's definition of IMPROPER
[more improper; most improper]
: not proper, right, or suitable不适当;错误的;不合适的: such as
b : not following rules of acceptable behavior : legally or morally wrong违法的;违规的;不正当的 c : not suitable for the situation : not appropriate不适当的;不合适的