Ubuntu forgot password How to do

Just installed, ubuntu14.04, just think, if forget login password, this can not do, so test under
Boot, just over the BIOS display screen, non-stop click, the keyboard left SHIFT key. (Because the beginning is the use of the way, the result is not the spirit.) So I keep clicking, failed, restart the machine, until using this method, keep clicking, come out successfully)
GRUB2, the picture is out.
Select Second: Ubuntu kylin gnu/linux Advanced Options
After entering another screen, select the second item
Ubuntu Kylin gnu/linux,with linux 3.13.0-24-generic (recover mode)
After entering the screen, select the Eighth option.
Root drop to root shell prompt


Last-action section
chmod 666/dev/null (chmod 666, all users have read and write access,)
Mount-o REMOUNT,RW/(Note:-O, this is the letter, not the 0, is the disk quota mount point for/partition.) RW is a read-write mode. The popular point, probably meaning, is to set the root partition to read-write mode. ）
chmod 777/etc/passwd (chmod 777, so the user has read and write execution permissions)
Pwconv (opens the user's shadow password.)
passwd root (note, root is user name)
Next, you enter the same password two times in a row.
The last merit became.

Ubuntu forgot password How to do