把宾语从句的从句部分提前是什么句式

把宾语从句的从句部分提前就变成了主语从句，原来主语变成宾语，谓语为被动语态(如原句为被动，这里则变为主动)。如：
He takes what he needs.
变成：
What he needs is taken by him.

That he ever said such a thing I simply don’t believe. （原句）
这句话语法不对，不严密。
主语是that引导的主语从句That he ever said such a thing，然后就只剩下I simply don’t believe，那就没有谓语了，改成正确的句子应该是：
That he ever said such a thing is what I simply don’t believe.
加上is what就对了。那么what I simply don’t believe是宾语从句，is做谓语。
而这句话正是I simply don't believe that he ever said such a thing.的宾语前置的结果。和我上面举的例子情形相同。也就是说，宾语前置可以通过把动词改为被动式be+v.ed或不改动词形态用BE+what的办法来变形。

宾语前置