A.fdisk/dev/sdb1 B.mkfs.ext4/dev/sdb1 C.mount/dev/sdb1 D.e2label/dev/sdb1ext4
A.fdisk B.e2label C.mkfs D.partprobe
A./dev/hda2 B./dev/sda1 C./dev/hda5 D./dev/sda5