In the reading passage, it indicates three possible usages of the "great houses" which are massive stone constructions.

In the reading passage, it indicates three possible usages of the " great houses" which are massive stone constructions. But the lecturer indicates that the three explanations could be totally wrong. And he gives specific details to support his opinion. The first theory is that Chaco building were used for purely residential contains hundreds of people for each. However, in the listening passage, the professor addresses that, even the outlook of the buildings are more like residential living places, the number of fire places is inconsistent with the theorem, which is fewer and the largest building could be used for one hundred families but the fire places could only be served for ten families. Hence, the giant building could not have function for pure dwellings. Secondly, Chaco structures could be used for storing maize since grain maize was the main crops of Chaco residents. However, inside the structures, there is no strong evidence of left maize or containers of maize. So, this storage theory could also be denied by the presenter. Finally, in the reading, it suggests the third possibility would be using for ceremonies, which is supported by the excavations of Pueblo Alto that revealed a huge amount of broken pots that be considered as evidence that people gathered together for ceremonial activities. Whereas in other deposits excavated from Pueblo Alto, there are some building materials such as sand, stone, even construction tools, which cannot be used for ceremonies and are more likely treated as trashes that people would have thrown away.