This assumes you can get the words into an array:

@x = qw[ this is the text to play with ];;

$n = 2; print @x[ $_ .. $_+$n-1 ] for 0 .. (@x - $n);;
this is
is the
the text
text to
to play
play with

$n = 3; print @x[ $_ .. $_+$n-1 ] for 0 .. (@x - $n);;
this is the
is the text
the text to
text to play
to play with

$n = 4; print @x[ $_ .. $_+$n-1 ] for 0 .. (@x - $n);;
this is the text
is the text to
the text to play
text to play with

$n = 5; print @x[ $_ .. $_+$n-1 ] for 0 .. (@x - $n);;
this is the text to
is the text to play
the text to play with
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