Whatdo you mean they are our replacements?
这句话是否不对，they are ourreplacements为何直接放在了mean后面，它是什么成分？另外这个句子可以加by吗？
What do you meanthey are our replacements?
这个句子语法不正确，但已经让人们所认同，应该看作正确的表达。其实，它看作是省略了 when you say 或by saying：
What do you mean （when you say）they areour replacements?
What do you mean （by saying）they areour replacements?
又如：
What do you meanyou can't do it? It'll be like shooting fish in a barrel!
你说干不了的意思是？这不是小事一桩嘛！
《牛津词典》
What do you meanyour mother is coming to stay for a week?
你说你母亲要来住一个星期的意思是？
What do you meanit doesn't feel right? 你说感觉不对劲的意思是？
【注】这个问题，还可以换一种思路去理解，即： mean 接双宾语。就是说，mean赋予给宾语从句的意思是。宾语从句为间接宾语，what 为直接宾语。如此处置，语法上就讲得通。
