open(D,"/usr/share/dict/words");@D=<D>;
$x=$D[int,rand()*$#D];$y=$D[int(rand()*
$#D)];$x=~s/'s\n$|s\n$|\n$//;$x.="s";$y
=~s/'s\n$|s\n$//;print"that $x my $y";#
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or an even *nix-ier way:

split/\n/,`cat /usr/share/dict/words`;$a
=$_[rand$#_];$a=~s/s$|$/s/;$b=$_[rand$#_
];$b=~s/s\n$//;print"that $a my $b";####
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and in a smaller but not the same way:

split/\n/,`cat /usr/share/dict/words`;print
"that ".$_[rand$#_]."'s my ".$_[rand$#_];##
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Don't know if smaller is possible