是three thousand\thousands of

three thousand还是three thousands 关于thousand、thousands、thousand of、thousands of thousand 、thousands、thousands of区别 是several thousand还是several thousands of ? thousand 与 thousands of thousand ,thousands,one thousand ,thousand of,thousands of a thousand ,thousands of ,thousand of 和thousands and thousan thousand,thousands,thousand of,thousands of的区别 thousand thousands thousand of thousands of 什么区别 thousand 与 thousands of 区别 要表示3000是three thousand还是three thousands?拜托各位大神 two thousand of 和thousands of 区别