Still guessing what your disklabel looks like, an example of
/etc/fstab might be

/dev/sd0a / ffs rw 1 1
/dev/sd0b none swap sw 0 0
/dev/sd0e /usr ffs rw 1 2
/dev/sd0f /home ffs rw 1 2
/dev/sd0g /var ffs rw 1 2

Patrick