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1·America has a very heterogeneous population.

美国人口是由不同种族组成的。

2·Cancer has long been viewed as a heterogeneous population of cells.

长时间以来，人们认为肿瘤由异质性肿瘤细胞群构成。

3·The population of the United States is vast and heterogeneous.

美国人口众多，人种混杂。