1、thousand与数词a\one\two等连用表示数量时，后面不加s。例如，a thousand metres一千米。two thousand people两千人。
2、thousands of 意为成千上万的。当thousand与of连用，必须在thousand后边加s，也就是thousans of，表姨胀兽辱示成千上万的。一些常见的短语例如，thousands of times千遍万遍，thousands of words千言万语，thousands of villages千村万落, thousands of households千家万户。例句：There are thousands of people die of cancer. 有成千上万的人死于癌症。
3、the thousands作为固定搭配时，意为达到千位数。例如，letters by the thousands. 数以千计的信件。例句：The cost of education runs into the thousands.教育的费用达到上千元。
