many thousands of还是many thousand of?不是three thousand这样说吗？two ______（thousand)of the books are sold out.
问题描述：
many thousands of还是many thousand of?
不是three thousand这样说吗？
two ______（thousand)of the books are sold out.
答
前者.
thousands of表示数千,加上many表示多的意思
three thousand表示三千,thousand表示具体数的时候不加S