慢速英语:Science of Safety: How Seat Belts, Kevlar Arrived

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2.patent n.专利, 专利权

例句：The patent runs out in three years' time.
      这项专利期限为三年。

专利品

例句：He owned several patents.
      他拥有几项专利发明。

3.attachment n.附着, 附属

例句：The attachment of the new engine to the car only took a few minutes.
      把新发动机装在汽车上只用了几分钟。

附属物, 附件

例句：The vacuum cleaner has four different attachments.
      吸尘器有四个不同的附件。

4.upper adj.较高的, 上部的
 
例句：He is a member of the upper house of legislature.
      他是上议院的成员之一。

5.extensive adj.广阔的, 广大的, 大量的; 广泛的, 大规模的, 广博的

例句：The house has extensive grounds.
      这栋房子有广阔的空地。