泛指的数目

ten, hundred, thousand, million, billion 等可以构成一些短语，表示泛指，意为数目多。这些词不能被具体数字修饰，但可被many, several, a few 等词修饰。

tens of 数十
hundreds of 数百
several hundreds of 成百上千
tens of hundreds 数千
thousands of 数千
tens of thousands of 上万
millions of 数百万
several millions of 数百万
several thousands of 上千
a few hundreds of 上百
millions of millions of 几万亿的
many millions of 好几百万
hundreds of hundreds of 数以万计的
thousands of thousands of 成千上万的