c:\@Work\Perl\monks>perl -wMstrict -le
"my $sentence = 'this is the text to play with';
 ;;
 my $ngramWindow_MIN = 1;
 my $ngramWindow_MAX = 3;
 ;;
 my @word_ngrams;
 ;;
 for my $ngramWindow ($ngramWindow_MIN .. $ngramWindow_MAX) {
   my $m = $ngramWindow - 1;
   my $ngram = qr{ \b [[:alpha:]]+ (?: \s+ [[:alpha:]]+){$m} \b }xms;
   ;;
   while ($sentence =~ m{ (?= ($ngram)) }xmsg) {
     push @word_ngrams, [ $1, $-[1] ];
     }
   }
 ;;
 for my $ar_wng (@word_ngrams) {
   my ($word_ngram, $sentence_offset) = @$ar_wng;
   print qq{'$word_ngram' at sentence offset $sentence_offset};
   }
"
'this' at sentence offset 0
'is' at sentence offset 5
'the' at sentence offset 8
'text' at sentence offset 12
'to' at sentence offset 17
'play' at sentence offset 20
'with' at sentence offset 25
'this is' at sentence offset 0
'is the' at sentence offset 5
'the text' at sentence offset 8
'text to' at sentence offset 12
'to play' at sentence offset 17
'play with' at sentence offset 20
'this is the' at sentence offset 0
'is the text' at sentence offset 5
'the text to' at sentence offset 8
'text to play' at sentence offset 12
'to play with' at sentence offset 17