my %words;
my %starting_words;

for my $i ( 0 .. $#words )
{
	my $cur_word = $words[$i];

	$words{$cur_word}++;
	if ( $words[$i-1] =~ /^[\.!\?]$/ )
	{
		$words{$cur_word}--;
		$starting_words{$cur_word} = $i;
	} # if
} # for