sub pl { $count == 1 ? 0 :1 } # check plural
 
my @s=("","s");
my @are=qw/is are/;
 
for $count (1..3) {
  print "There $are[pl] $count piece$s[pl] of pizza left!\n";
}

##</code><code>##

There is 1 piece of pizza left!
There are 2 pieces of pizza left!
There are 3 pieces of pizza left!