I wish, in addition,  that I could remember and forget something as I please,  just like the way a computer stores the document.  That's because I participated in an exam these days,  during which I once forgot some important knowledge so I want a better memory; but ironically, I also thought something happened again and again,  making myself hard to fell asleep,  which is why I'd like an oblivion. 

回复 @啊啊是谁都对：Er…that's really a big problem.

But when you delete a file in computer it can't be restored, right? So do I

回复 @啊啊是谁都对：I hope so but it actually not.