蛮不讲理

Explanation: Rude and unreasonable. 　　Usage: Partial official; as predicate, attributive, adverbial; containing derogatory 　　Source: Mao Zedong's "On the Correct Handling of Contradictions Among the People": "In our society, there are few despite the public interest, being unreasonable, the perpetrators who break the law." 　　Examples: In our society, there are few despite the public interest, ~, the murderers who break the law. (Mao Zedong's "On the Correct Handling of Contradictions Among the People") Thesaurus:  Obliquity reason, pester sb. endlessly, Outrageous, sophistication, Dumbness To on, in one's mouth pester, to look for trouble