Short of not using a cellphone, the lowest exposure would come from using the speaker phone or a wired headset or ear buds.

减少与手机接触的最有效方法是使用手机的扩音器、有线耳机或耳麦。

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D.C. police will pull you over if they see you using a cellphone that you’re holding up to your ear, but not if you’re hands-free.

如果发现你在车上把手机放在耳朵旁，华盛顿警方将截停你在路边，但如果你使用免提电话，他们就不会。

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A separate NHTSA report estimates that at any given time in 2007, there were more than one million U. S. drivers using a cellphone while driving.

国家公路交通安全局单独报告估计，在2007年任何一个时间，都有一百多万美国司机开车打手机。

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But if you don't have a PDA, accessing and sending e-mail using a cellphone is still a major hassle.

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It was not clear what the detonation device was, but the charges against Dzhokhar say he was using a cellphone moments before the blasts.

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Even simply using a cellphone was banned at the concert thrown by phone-maker Samsung, though promoters worked the crowd beforehand, offering customers fresh phone batteries or device test-drives.

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