First of all, it is its touching plot and unique theme what caused my decision to recommend it to you.这里用it作形式主语指代what引导的名词性从句可以嘛?因为同学和我说只能用that取代what作强调句。还有caused my decision可以这么说吗?
Raise your hand if you had never heard of Tetralogy of Fallot with pulmonary atresia before Monday's episode of ABC's Jimmy Kimmel Live.上句中的had never heard of是虚拟语气吗,表达怎样的含义?谢谢老师的回答。