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　　As early as the twelfth century A.D., the settlements of Chaco Canyon in New Mexico in the American Southwest were notable for their “great houses,” massive stone buildings that contain hundreds of rooms and often stand three or four stories high. Archaeologists have been trying to determine how the buildings were used. While there is still no universally agreed upon explanation, there are three competing theories.
　　早在12世纪，美国西南部墨西哥地区查科峡谷的居民就以他们的“巨屋”而闻名。这种石质材料建成的“巨屋”包好有数百个房间，而且通常有三到四层高。很多考古学家都试图解释这些建筑的用途。尽管业界尚未达成一致，但现在有三个比较有竞争力的理论。

　　One theory holds that the Chaco structures were purely residential, with each housing hundreds of people. Supporters of this theory have interpreted Chaco great houses as earlier versions of the architecture seen in more recent Southwest societies. In particular, the Chaco houses appear strikingly similar to the large, well-known “apartment buildings” at Taos, New Mexico, in which many people have been living for centuries.
　　一个理论认为这些巨屋是单纯用来居住的，每个可以容纳数百人。持有这种理论的人解释说查科巨屋同时间较近的一些西南族群早期建筑的雏形。尤其值得一提的是，查科的这些建筑同新墨西哥陶斯镇著名的“寓所式建筑”非常相似。这些寓所式建筑供很多人居住了数个世纪。

　　A second theory contends that the Chaco structures were used to store food supplies. One of the main crops of the Chaco people was grain maize, which could be stored for long periods of time without spoiling and could serve as long-lasting supply of food. The supplies of maize had to be stored somewhere, and the size of the great houses would make them very suitable for the purpose.
　　第二个理论认为查科建筑是用来储存食物的。查科人的主食之一是玉米。玉米可以不宜变质，可长期储存，因此可以作为长期的食物来源。这些玉米一定是要储存在某个地方的。而巨屋的规模非常适合作为储存地。

　　A third theory proposes that houses were used as ceremonial centers. Close to one house, called Pueblo Alto, archaeologists identified an enormous mound formed by a pile of old material. Excavations of the mound revealed deposits containing a surprisingly large number of broken pots. This finding has been interpreted as evidence that people gathered at Pueblo Alto for special ceremonies. At the ceremonies, they ate festive meals and then discarded the pots in which the meals had been prepared or served. Such ceremonies have been documented for other Native American cultures.
　　第三个理论认为这些房屋是用来作祭司中心的。离一个巨屋不远的地方有个阿尔托村庄，考古学家在那里发现了一个由古代材料堆积成的山包。对这个山包挖掘后发现了大量破碎罐子。这个发现佐证了人们聚集到巨屋是为了某种祭祀。在祭祀中他们使用节日佳肴，然后把做饭和盛食物的器皿抛弃。而这样的祭祀活动在其他美洲土著文化中有所记载。

　　阅读部分需要提取的观点是
　　这篇文章从结构和内容上看，都比较和谐。但是，考古学的内容可能比较陌生，但是，更多是心理战的成分。
　　- Main point: 查科峡谷巨屋的用途。
　　- Sub point 1:居住。
　　- Sub point 2:储存玉米。
　　- Sub point 3:祭祀。