A liar is always lavish of oaths liar, always, lavish, oaths

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A liar is always lavish of oaths. ----- Corneille
　　骗子从不吝啬誓言。----高乃依
　　lavish in/of /with sth means giving or producing generously or in large quantities.是指慷慨的，大方的意思。例如：He was lavish with his praise for/lavish in praising the project.他对那计划赞不绝口。
　　另外，lavish sth on/upon sb/sth也是一个固定的用法。It means give sth to sb/sth abundantly and generously.是指慷慨而大量地将某物给某人(某事物)。例如：lavish care on an only child.对独生子女关怀备至。