>perl -wMstrict -le
"my @motifs = qw(WEED KILLD DIAL PIES);
 my $motif = join '|', @motifs;
    $motif = qr{ $motif }xms;
 ;;
 my $element = 'both WEED PIES and DIAL PIES are present';
 ;;
 my %elements =
   map { $_ => 1 }
   $element =~ m{ $motif }xmsg
   ;
 ;;
 printf qq{$_ is %spresent \n}, $elements{$_} ? '' : 'NOT '
   for @motifs;
 ;;
 my @present = keys %elements;
 print qq{present: @present};
"
WEED is present
KILLD is NOT present
DIAL is present
PIES is present
present: WEED DIAL PIES