She must have some ulterior motive for being nice to me—what does she really want?

她对我这么好，一定别有用心—她到底想干什么呢？

《牛津词典》

The disposals being forced on RBS owe little to competition or viability concerns and quite a bit to the punishment motive.

强加给RBS的处置并不是因为竞争或生存能力方面的考虑，更多是因为惩罚动机。

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Without good effect, any motive is inadvisable, no matter how noble it is. In the same way, without being restricted by purposes, good measures may lead to bad behaviors.

离开良好的效果，无论动机如何崇高都是不可取的，同样，离开目的对手段的制约，那么，手段也可能导致恶行。

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"Holly, you can tell, had this ulterior motive every minute being at the Mansion, and that motive was -- it was clear as day -- she wanted Hef's kids, she wanted a piece of Playboy and she wanted to marry Hef for, obviously, his will, " Wilkinson told People magazine.

CNN: Former Playboy girlfriends feud

The politician said that "money or financial gain" had never been a motive for him and stressed that the social inquiry report had assessed him as being of low risk for harm to the public and for re-offending.

BBC: Tommy Sheridan jailed for three years for perjury

The Profit Motive in Education provides a unique glimpse into the potentially transformative power of private sector involvement in education, providing the reader with persuasive evidence supporting the claim that the profit motive can be harnessed to meet the needs of future generations that are not currently being met by the static education models of the past.

FORBES: Harnessing the Profit Motive to Transform Education