按shift不会让我进入任何grub菜单
我需要进入恢复模式，但按下并按住shift在启动时不起作用，我也试过点击shift和f8但没有任何反应，有什么建议吗？ 我的系统运行ubuntu 14.04，这是我的grub文件：
# If you change this file, run 'update-grub' afterwards to update # /boot/grub/grub.cfg. # For full documentation of the options in this file, see: # info -f grub -n 'Simple configuration' GRUB_DEFAULT=0 GRUB_HIDDEN_TIMEOUT=5 GRUB_HIDDEN_TIMEOUT_QUIET=true GRUB_TIMEOUT=10 GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian` GRUB_CMDLINE_LINUX_DEFAULT="quiet splash" GRUB_CMDLINE_LINUX="" # Uncomment to enable BadRAM filtering, modify to suit your needs # This works with Linux (no patch required) and with any kernel that obtains # the memory map information from GRUB (GNU Mach, kernel of FreeBSD ...) #GRUB_BADRAM="0x01234567,0xfefefefe,0x89abcdef,0xefefefef" # Uncomment to disable graphical terminal (grub-pc only) #GRUB_TERMINAL=console # The resolution used on graphical terminal # note that you can use only modes which your graphic card supports via VBE # you can see them in real GRUB with the command `vbeinfo' #GRUB_GFXMODE=640x480 # Uncomment if you don't want GRUB to pass "root=UUID=xxx" parameter to Linux #GRUB_DISABLE_LINUX_UUID=true # Uncomment to disable generation of recovery mode menu entries #GRUB_DISABLE_RECOVERY="true" # Uncomment to get a beep at grub start #GRUB_INIT_TUNE="480 440 1" 如果密钥不起作用，您实际上可以编辑grub config文件，以便您有一点暂停。
sudo gedit /etc/default/grub
将GRUB_HIDDEN_TIMEOUT的值更改为以秒为单位的数字。 例如，如果将其从0更改为10，则会在自动启动第一个选项之前显示Grub菜单10秒。
完成所需更改并保存文件后，将其关闭并运行以下命令以应用更改：
sudo update-grub
之后
sudo reboot