Old batteries can't be discarded casually even when they are no longer useful, because they'll pollute the environment.

旧电池即使没用了也不能随意丢弃，因为它们会污染环境。

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We have to recycle old batteries.

我们必须回收旧电池。

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Next, take any coating and tops off your old batteries and move them carefully onto the new ones.

其次，把旧电池上的外层和顶部小心的移装到新电池上。

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Tempers are running high over the Coast Guard's belated effort to recover thousands of old batteries, containing toxic materials, which it dumped between the 1920s and the 1970s in waterways all over the country.

ECONOMIST: The Coast Guard: Keeping all channels open | The

Al Terrile, a 69-year-old retired Southport resident, stocked up on batteries, a box of firewood and a light at the hardware store.

WSJ: Sandy in back of Easterners' minds as snow falls

And, even if the batteries die, you can still use the old standby: an actual key.

ENGADGET