forget to do sth忘记做某事了(这件事情没有做)
forget doing sth忘记做过了某事(这件事情做了)
remember to do sth记得去做某事(还没做)
remember doing sth记得做过了某事 (已经做了)
I remember closing the window when I left here.
I remember that I had closed the windows when I left.
i remembered that i closed the windows when i left.
I remember that I had shut the window before I left.
绝对正确