In C mode, that's what I usually do, only slightly different:

printf ("%d %s%s\n", $count, "cat", ($count==1)?"":"s");
printf ("%d %s%s\n", $count, "cact", ($count==1)?"us":"i");
printf ("%d %s%s\n", $count, "Elvi", ($count==1)?"s":"i");
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As an alternative, you might want to use:

print $count, "cat", (($count==1)?"":"s"), "\n";
print $count, "cact", (($count==1)?"us":"i"), "\n";
print $count, "Elvi", (($count==1)?"s":"i"), "\n";
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Or perhaps as a method:

sub quantize
{
     my ($quantity, $singular, $plural) = @_;
     return (1==$quantity)? $singular : $plural;
}

$count = 2;

print "$count @{[quantize($count,'cat','cats')]}\n";
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