#!/usr/bin/perl
use Data::Dumper;

my %hash = ('Abend' => 'NN',
            'Sonne' => 'NN',
            'Haus' => 'NN',
            'Abendsonne' => 'who knows',
);

while (<DATA>) {
        chomp;
        $hash{$_}="irgendwas";
}

#print Dumper \%hash;


for my $word ( keys %hash ) {
    for my $pre ( keys %hash ) {
        for my $post ( keys %hash ) {
            if ( lc $word eq lc "$pre$post" ) {
                print $word, $/;
            }
        }
    }
}



__DATA__
!
#
$
%
&
'
(
)
*
+
+16,4%
+23%
+5,8%
+8,8%
,
-
[...]
[...]

[...]
£
©
±
µg/m
«
»

#!/usr/bin/perl
use strict;
use warnings;
use Data::Dumper;

my %hash = ('Abend' => 'NN',
            'Sonne' => 'NN',
            'Haus' => 'NN',
            'Abendsonne' => 'who knows',
);


my %klein= map {(lc $_ => $_)} keys %hash;


my @woerter=keys %klein;

for my $pre ( @woerter ) {
        for my $post ( @woerter ) {
                my $kompo = $pre.$post;
                if ( $klein{$kompo} ) {
                        print "$kompo \t $klein{$kompo} \t $hash{$klein{$kompo}} \n";
                }

        }
}