While the name doesn't suggest being useful, you might find Lingua::LinkParser beneficial. It not only parses sentences, but also identifies each word's role in the sentence -- or how the words link together. Thus, you'll know a sentence about the "dog days of summer" isn't about dogs. You can read a detailed intro here.

The module (the core of which integrates with C code that you install separately), generates data structures that break a sentence down into component parts, though there's a bit of work you' have to do to wade through all the types it lists. Here's a short example (the module has docs for all of those link types):

use Lingua::LinkParser;
use strict;

my $parser = new Lingua::LinkParser;        # create the parser
my $text   = "Moses supposes his toses are roses.";
  
my $sentence = $parser->create_sentence($text); # parse the sentence
my $linkage  = $sentence->linkage(1);        # use the first linkage
  
print $parser->get_diagram($linkage);         # print it out

__END__
    +-------------------------Xp------------------------+
    |                +------Ce------+                   |
    +---Wd--+---Ss---+      +--Dmc--+--Spx--+--Opt-+    |
    |       |        |      |       |       |      |    |
LEFT-WALL Moses supposes.v his toses[!].n are.v roses.n .
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