supererogatory: implies a giving above or beyond what is required by rule and may suggest the adding of something not needed or not wanted: an abrupt man who regarded the usual pleasantries as ~.                      pleasantry客气话客套


gratuitous: may apply to a voluntary giving without expectation of return: provided ~ services; but usually applies to something offensive or unpleasant given or done without provocation: a ~ insult.     义项2又如there's too much crime and gratuitous violence on TV电视里充斥着犯罪和无谓的暴力，如本例a gratuitous insult无端(无缘无故)的侮辱       义项1又如we often mistake the gratuitous blessings of Heaven for the fruits of our own industry我们常把上天无偿的恩赐误以为是自身勤劳的果实，gratuitous distribution/legal advice免费配给/法律咨询。名词gratuity表示小费an amount of money giving to a waiter or waitress for performing a service，如a 15 percent gratuity百分之十五的小费，也叫tip


uncalled-for: implies a gratuitous impertinence or logical absurdity: resented her ~ advice.  又如uncalled-for jealousy无谓的妒忌     impertinent无礼的不敬的，多指没有礼貌地问问题或表示好奇a little brat asking impertinent questions一个小顽童问无礼的问题；absurd荒唐=not reasonable


wanton: implies not only a lack of provocation but a malicious, arbitrary, or sportive motive: the ~ destruction of property by vandals.   sportive嬉戏的取乐的=playful   (wanton 1无理任性肆意implies causing harm or damage deliberately and for no acceptable reason，如wanton aggression/luxury肆意侵略/大肆奢华, wanton destruction of environment肆意破坏环境, wanton disregard for his friend's feelings全然不顾他朋友的感受  2放荡not sexually moral or respectable, 用于wanton woman荡妇)


supererogatory份外的多余的: 指超出职责义务，或多余的，gratuitous无偿的无谓的: 指免费提供的，但更多指无缘无故地令人不快的，uncalled-for无谓的: 指既不必要也不恰当，wanton肆意: 指武断恶意随心所欲

记忆方法: 1) 无谓的意思是无缘无故无必要不恰当mean done without need, compulsion, warrant, or provocation.

提供例句就好了。

Thanks so much!

you are welcome