A A stone kills two birds.

一箭双雕，一石二鸟。

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This way, not only does employee loyalty improve, but customers also become more loyal clientele; such a policy kills two birds with one stone for a win-win situation.

这样一来，不但提升了员工对企业的忠诚度，而且加强了客人的消费黏度，一举两得，获得了双赢。

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Hitachi is working with Nippon Signal and the University of Yamanachi to build a new boarding gate that hopefully kills those two security birds with one stone.

ENGADGET: Hitachi boarding gate can sniff explosives on passes, keep the transport queues flowing (video)