History is full of examples of people who play it too safely. They live their lives without risking for something better.

历史上有许多人都过着平静的生活，他们从不为争取更好的结果冒险。

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Greg Bower(ph), of the International Association of Bomb Technicians and Investigators, says nitroglycerin is usually too unstable to handle safely.

NPR: It's Hard to Spot a Liquid Threat to Airline Safety

In case you've still not pieced it together, there are simply too many variables to safely say that one provider is right for every fan of HD.

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The moans about their inability to make profits safely sounds all too close to the noises from old-style airlines before the arrival of low-cost carriers.

ECONOMIST: Bank regulations