#! perl -sw
use strict;

our $WORDS ||= 1;
our $KEYWORD || die "-KEYWORD=word needed";

local $/ = ''; # Paragraph mode

my $re_word = qr[\S+\s+];

my $re_5w_key_5w = qr[
	(
		$re_word {1,$WORDS}
		\Q($KEYWORD\E[,.;:!?]*\s+
		$re_word {1,$WORDS}
	)
]ix;

open IN, '<', $ARGV[ 0 ] or die $!;

while( <IN> ){
	if( $_ =~ $KEYWORD ) {
		while( $_ =~ m[$re_5w_key_5w]g ) {
			print "'$1'\n---\n";
		}
	}
}