你定语从句掌握不太好啊,你看啊,the reason做的是gave的宾语吧,he gave the reason for his absence,宾语的先行词不是只有that which 吗,不要一看到reason就想选why.
再给你个用why的,你自己区别一下:I’d like to know the reason why you’re so late.
再给你一个:We aren’t going for the simple reason that we can’t afford it.同位语从句