Ошибки зависимостей и сценариев после установки для пакетов GRUB и EFI

Я пытаюсь установить несколько вещей, используя apt-getно у меня проблемы.

Когда я печатаю sudo apt-get install <something> Я всегда получаю это:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
chrome-gnome-shell is already the newest version (10-1).
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
3 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue? [Y/n] 
Setting up grub-pc (2.02-2ubuntu8.6) ...
/var/lib/dpkg/info/grub-pc.config: 34: /etc/default/grub: Syntax error: EOF in backquote substitution
dpkg: error processing package grub-pc (--configure):
 installed grub-pc package post-installation script subprocess returned error exit status 2
dpkg: dependency problems prevent configuration of grub-efi-amd64-signed:
 grub-efi-amd64-signed depends on grub-efi-amd64 | grub-pc; however:
  Package grub-efi-amd64 is not installed.
  Package grub-pc is not configured yet.

dpkg: error processing package grub-efi-amd64-signed (--configure):
 dependency problems - leaving unconfigured
dpkg: dependency problems prevent configuration of shim-signed:
 shim-signed depends on grub-efi-amd64-signed; however:
  Package grub-efi-amd64-signed is not configured yet.

dpkg: error processing package shim-signed (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
                          No apport report written because the error message indicates its a followup error from a previous failure.
                                                    Errors were encountered while processing:
 grub-pc
 grub-efi-amd64-signed
 shim-signed
E: Sub-process /usr/bin/dpkg returned an error code (1)