if you want more concise code you could take advantage of the fact that while interpolating arrays/hashes indices/keys are evaluated.¹

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";
}
[download]

gives

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

This approach is quite flexible if you need to handle irregular plurals like @children=qw(child children)

HTH!

PS: if you wanna get rid of the pl() function you could use tied arrays evaluating index $count.

UPDATE: cleaned code...

1) yes eval is not the only backdoor for code injection ...