它这个词的理解,就相当于people,family之类的,可以当单数或者不可数名词,也可以当复数,集体名词来理解。people作为人,人民就是复数概念,谓语动词用原形,但是当作民族来理解,它集体单数,多个民族就得用peoples类同的是:the population of the world is …China has a population of …也有populations.(在表示多个地区的人口时,population要用复数形式populations。例如:Many parts of the world, which once had large populations and produced plenty of crops, have become deserts.)翻了下牛津字典,解释的是[C+sing./pl.v.,U](可数名词,谓语动词有单数或者复数形式,或者不可数名词)