$ sudo apt-get install grub2

# 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=        #本项留空
GRUB_HIDDEN_TIMEOUT_QUIET=  #本项留空
GRUB_TIMEOUT=10             #grub菜单显示的秒数
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=1280x1024

# 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"

$ sudo vim /etc/grub.d/30_os-prober

make_timeout () {
  if [ "x${found_other_os}" = "x" ] ; then
    if [ "x${1}" != "x" ] ; then
      if [ "x${GRUB_HIDDEN_TIMEOUT_QUIET}" = "xtrue" ] ; then
    verbose=
      else
    verbose=" --verbose"
      fi

      if [ "x${1}" = "x0" ] ; then
    cat <<EOF
if [ "x\${timeout}" != "x-1" ]; then
  if keystatus; then
    if keystatus --shift; then
      set timeout=-1
    else
      set timeout=10 #第一处
    fi
  else
    if sleep$verbose --interruptible 3 ; then
      set timeout=10 #第二处
    fi
  fi
fi
EOF
      else
    cat << EOF
if [ "x\${timeout}" != "x-1" ]; then
  if sleep$verbose --interruptible ${GRUB_HIDDEN_TIMEOUT} ; then
    set timeout=10 #第三处
  fi
fi
EOF
      fi
    fi
  fi
}

$ sudo update-grub