The phrase "telling lies" is most likely a gerund that works as a noun in the sentence.
This is a word that ends in -ing resembling a verb but has a different function, for example, they can work as nouns.
This can work as a gerund in sentences such as "Teling lies has negative consequences" because despite ending in -ing is does not act as a verb but as a noun.
Learn more about gerund in: https://brainly.com/question/11017355
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