#print
As with other commands, you can specify a line
number in front of the 's' command.  Thus
  3s/x/a/
will change the first 'x' to an 'a' on the third line
of the current file.  Pick up file 'town' and
change the 'q' on the last line to a 'p'.  Then
rewrite the file and type 'ready'.
#create Ref
south orange
maplewood
millburn
short hills
summit
new providence
#create town
south orange
maplewood
millburn
short hills
summit
new qrovidence
#user
#cmp town Ref
#log
#next
31.1a 10