>perl -wMstrict -le "my $s = qq{foo \n bar \n baz \n fee \n fie \n foe \n aa \n bb \n cc \n}; print qq{[[$s]]}; ;; my @fields = split m{ (?: [^\n]* \n){3} \K }xms, $s; print qq{[[$_]]} for @fields; " [[foo bar baz fee fie foe aa bb cc ]] [[foo bar baz ]] [[ fee fie foe ]] [[ aa bb cc ]]