BE ON TO

{v. phr.} To understand the motives of someone; not be deceived. * /Jack keeps telling us how wealthy his family is, but we are on to him./

{v. phr.} To understand the motives of someone; not be deceived. * /Jack keeps telling us how wealthy his family is, but we are on to him./

раскусить кого-л.; раскрыть уловку

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