曹老师，你好，我读了你的 [比较分句than what中what保留还是删去] 文章后，今天读外刊遇见一个句子，It argues thatthe bet against subprime mortgages was far riskier than is often appreciated.
这里的比较项应为形容词比较级riskier，但than分句中缺少的主语并非比较对应项riskier吧。所以这里是否应该为than what isoften，这是外国编辑写错了吗?
It argues that the bet against subprimemortgages was far riskier than is often appreciated.
假如把than理解为连词在从句中不作成分，than分句保留谓语动词而省略主语只能是下面二种状况之1、
1 省略的主语为比较对应项；
2 省略的主语为嵌入分句（即形式主语it和外置的that从句或不定式分句）。
本句中than分句省略的主语就是嵌入分句，把补全省略后为：
Itargues that the bet against subprime mortgages was far riskier than it is often appreciated thatit would be.
Appreciate在此意为realize。That从句的主语it指代thebet against subprime mortgages。That从句的表语为比较对应项，需要省略。
所以这个句子是正确的句子。Than后面不可加what.加what被觉得是uneducated。
