have an ulterior motive

I have an ulterior motive in offering to help you.

我主动提出要帮助你是有私心的。

《牛津高阶英汉双解词典》

They are probably not sincere and have an ulterior motive.

因为他们并不诚挚,而且可能别有用心.

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With the wide application of the Internet of things, if the Internet of things technology once have an ulterior motive of people use consequences be unbearable to contemplate. National information disclosure may threaten national security. The loss of business information will cause inestimable losses to businesses.

随着物联网的广泛应用，如果物联网技术一旦被别有用心的人利用，后果不堪设想；国家信息泄露可能会威胁到国家的安全，商业信息的丢失会造成不可估量的商业损.失。

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Of course, we cannot underestimate the enemy agents, domestic separatist forces and a few extremists took the opportunity to have an ulterior motive "floating" failure, trouble, trouble energy.

当然，我们不能低估国内敌特分子、分裂势力以及少数别有用心的极端分子趁机“浮动”破坏、捣乱、滋事的能量。

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A cynic reckons that people generally have an ulterior motive for what they do.

他们认为通常情况下，人们做事都是别有用心的。

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Still, this means the designers can continue their dialogue without worrying about food coming out of their mouths, so maybe they have an ulterior motive.

然而，这意味着他俩可以继续对答，同时无需担心吃的东西从嘴巴里掉出来，或许是他们别有用心。

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