the reason why 和the reason is that 的区别在哪,他们引导的从句是不是都不缺成分

the reason why…是由why引导定于状语从句,在句中作引导词,不能省略.例：The reason why some people ask is that they have questions.（人们问的理由是他们有疑惑.）
the reason is that 是由that 引导的表语从句,that位于be动词之后,也做引导词,不能省略.例：The reason is that he has had a headeache.(原因是他头痛.）
再问： 请问。那有the reason that这样的 吗
再答： 没有这种情况哈