undiplomatic
adj. 无外交策略的
例句
He could be the most undiplomatic man ever to hold such a post.
他可能是在这个位置上工作过的人中最不善交际的。
《柯林斯英汉双解大词典》
UNDIPLOMATIC: Your performance has been poor lately.
不得体表达:你最近的表现比较差。