YOU SAID:
[4] mount -t tmpfs mdev /dev [5] mkdir /dev/pts [6] mount -t devpts devpts /dev/pts
INTO JAPANESE
[4] マウント -t tmpfs mdev /dev [5] mkdir /dev/pts [6] マウント -t devpts devpts /dev/pts
BACK INTO ENGLISH
[4] mount -t tmpfs mdev /dev [5] mkdir /dev/pts [6] mount -t devpts devpts /dev/pts
INTO JAPANESE
[4] マウント -t tmpfs mdev /dev [5] mkdir /dev/pts [6] マウント -t devpts devpts /dev/pts
BACK INTO ENGLISH
[4] mount -t tmpfs mdev /dev [5] mkdir /dev/pts [6] mount -t devpts devpts /dev/pts
That didn't even make that much sense in English.