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I just boot up my laptop then run the
sudo apt-get update command, but there's an error says:
[username] is not in the sudoers file. This incident will be reported.
so I search the google for solution and it told me to go to the recovery mode on boot menu.
After I got there,the recovery mode option didn't exist. I searched again for another way, then I found some source says change the kernel option with single on linux line on boot menu. Well, I got problem while deleting the kernel option, which one is it?
If the code is:
Linux /vmlinuz-3.13.0-44-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash $vt_handoff
which part should I delete?
Anyway, I'm using the ubuntu 14.04; the grub version is 2.2 beta I believe.