thousand既是可数名词也是不可数名词。

thousand

num.一千;数以千计的;成千上万的;许许多多的;1 000到9 999间的数目;千位数

复数： thousands

A thousand people were there.

那里有一千人。

A thousand dollars is nothing to somebody as rich as he is.

一千英镑对于像他这么富有的人来说算不上什么。

The system produced enough energy to heat several thousand homes.

系统产生的能量足以给几千户人家供暖。