There are two other kinds of research that have thrown some light on the origins of the Native American population; they involve the study of teeth and of languages.

还有另外两种研究对印第安人的起源提供了一些线索；它们包括对牙齿和语言的研究。

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Some languages would require more than a year of study for a native English speaker, while others would take just weeks.

有些语言对于英语母语者来说需要花一年多去学习，而有的语言只需花几周。

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An increasing number of people take up the study of Japanese every year, bringing with them an increasing diversity of native languages and goals in studying Japanese.

随着学习日语的人数逐年增加，其母语及学习目的也趋于多样化，随之出现了各种形式的日语学习书籍。

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Whorf never got an advanced degree, but he took graduate classes in his free time with the anthropologist and linguist Edward Sapir, in the nineteen-thirties, and he devoted his leisure hours to the study of Native American languages.

NEWYORKER: Utopian for Beginners