4．Chaco Great House
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．
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．
A second theory contends that the Chaco structures were usedto 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 a 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．
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．
For Reference：
While the precise function of Chaco great houses remains uncertain，there are three conflicting hypotheses．Firstly，they were supposed to be the houses for the similarity to later apartment buildings in New Mexico．Secondly，they were used for the storage of main crops．Thirdly，houses were considered to have held the ceremonies，based on the broken pots unearthed around．（59 words）
The ancient settlements of Chaco Canyon，famous for great stone houses，remain mysterious as for their functions．First，they might be residential for apparent connection to Taos'．Alternative explanations include storing maize to secure food sources which require huge space and extended period．Finally，the ceremonial purpose is traced with the broken pots for festive meals documented in native culture．（60 words）．
分析 写好这类作文要注意几个步骤：1． 认真审题，找准提示语中的关键词或句，确定中心思想．2． 依据关键句，草拟提纲，梳理文章的脉络3． 准确定位人称、时态．注意使用高级词汇和高级句型使文章显得更有档次．4．最后还要认真查验是否有漏写情况，有无拼写错误及标点误用等
高分句型一：
While the precise function of Chaco great houses remains uncertain，there are three conflicting hypotheses
在查科大房子的确切功能尚不确定时，这里有三个相互矛盾的假设．
高分句型二：
Alternative explanations include storing maize to secure food sources which require huge space and extended period．
其他的解释包括存储玉米安全的食物来源的可信度，需要巨大的空间和较长的时间．
解答 For Reference：
While the precise function of Chaco great houses remains uncertain，there are three conflicting hypotheses（高分句型一）．Firstly，they were supposed to be the houses for the similarity to later apartment buildings in New Mexico．Secondly，they were used for the storage of main crops．Thirdly，houses were considered to have held the ceremonies，based on the broken pots unearthed around．（59 words）
The ancient settlements of Chaco Canyon，famous for great stone houses，remain mysterious as for their functions．First，they might be residential for apparent connection to Taos'．Alternative explanations include storing maize to secure food sources which require huge space and extended period（高分句型二）．Finally，the ceremonial purpose is traced with the broken pots for festive meals documented in native culture．（60 words）
点评 开放性作文给出一定的写作主题，并此为基础进行思维和联想，自由发挥．不仅考查学生在内容、结构安排、语言运用和组织方面的能力，而且对学生的想像力、发散思维、归纳判断能力也有很高的要求．
