One of the problems with harvesting sunlight is that the sun's rays can be highly destructive to many materials. Sunlight leads to a gradual degradation of many systems developed to harness it.

太阳能技术面临的一个大问题在于，阳光对许多材料损害性很大，能让许多获取太阳能的系统缓慢失效。

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Even many valuable materials like silver can be used to make chopsticks.

甚至许多贵重的材料，如银，都可以用来做筷子。

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There are many varieties and grades of paper materials, and whilst it is fairly easy to spot the varieties, it is far more difficult to spot the grades.

纸张材料有许多品种和等级，虽然很容易分辨它们的种类，但要分辨它们的等级就困难得多了。

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But that is changing. There are many different kinds of materials and styles used to make furniture.

VOA: special.2010.12.10

There are many shapes, colors and materials to choose from.

VOA: special.2009.02.16

Prosecutors are investigating why so many modern buildings were flattened by the quake and whether flawed construction materials were to blame.

VOA: standard.2009.04.12

This is why using a web based service to send out printed materials is still attractive to many business owners.

FORBES: How Amy Promotes This Old House

Nicolai and I discussed how he used many common materials to decode and open locks.

FORBES: A Former KGB Covert Entry Expert Speaks

Plans to tear up 300 miles of the worst roads in Surrey and rebuild many of them with materials designed to last a decade have been unveiled.

BBC: Pothole