在 Ubuntu 启动期间（记不清了，但不高于 16.04）
我收到错误
Minimal Bash-like line editing is supported. For the firs word, TAB list possible command completions. Anywhere eise tab list possible device or file completions
grub>
尝试通过以下方式修复此问题此俄语说明来自 help.ubuntu.ru。
笔记：英文版本可在 help.ubuntu.com 上找到。
Disk /dev/loop0: 1.5 GiB, 1612648448 bytes, 3149704 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
The primary GPT table is corrupt, but the backup appears OK, so that will be used.
Disk /dev/sda: 465.8 GiB, 500107862016 bytes, 976773168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: 97EC9BD5-12A2-4852-94C0-30BAB6C4FD4A
Device Start End Sectors Size Type
/dev/sda1 2048 1050623 1048576 512M EFI System
/dev/sda2 1050624 960630783 959580160 457.6G Linux filesystem
/dev/sda3 960630784 976771071 16140288 7.7G Linux swap
这sudo mount /dev/sda2 /mnt
给出
mount: special device /dev/sda2 does not exist
请帮我。