最近在中国旅行时,美国的教授们发现,河南,广西,陕西,山西等省的居民们长期来就在黄土山中建造掩土住房以利用地下空间。自古以来,人们就用简单的手工工具在松软的土壤中建造这种掩土房屋。实际上,毛泽东也在这样的房屋中住过一小段时间。今天,据说有成百万的人们在地下的厅房中居住。在有些地区地下空间不但用于居住,而且还用作工厂、学校和政府机关。 During a recent trip to China, professors in the United States discovered that residents of provinces such as Henan, Guangxi, Shaanxi, and Shanxi have long been building sheltered houses in the Loess Mountains to use underground space. Since ancient times, people have used simple hand tools to build this sheltered home in soft soil. In fact, Mao Zedong lived in such houses for a short period of time. Today, millions of people are said to live in underground halls. In some areas underground space is not only used for living but also used as factories, schools and government agencies.