Notes：
bicycle messengers 自転車配達人(自転車で書類や小荷物などを配達する人);
vitally 極めて;
on commission 歩合制で;
incentive やる気, 意欲;
zoom in and out of traffic 猛モースピードで人や車の往来に入ったり，出たりする;
precarious 危なっかしい, 不安定な;
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New York City is full of people and traffic. That’s why there is an amazing delivery service — bicycle messengers. The messengers ride their bicycles all across the city, delivering important documents and packages from one place to another. They are faster than cars, and this makes the job vitally important but also dangerous. The messengers get paid on commission, so they have a lot of incentive to go at high speeds. But, because of this, bicycle messengers have 13 times as many serious accidents as other people. The next time you watch a show about New York, see if you can see a messenger zooming in and out of traffic. Then you will really understand how precarious their jobs can be.
(by Prof. Carmella Lieske)
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