Marcello,
You do not say what marks the end of a sentence. In english, there are many ways to do this (period, question mark, exclamation mark, etc). Also, your regex does not look like it should work by your specifications. This will also break on the sentence "How are you today Dr. Smith?" 
#!/usr/bin/perl
use strict;
use warnings;

my $msg = "One bright day in the middle of the night,\n";
$msg .= "two dead men got up to fight.\n";
$msg .= "Back to Back they faced each other,\n";
$msg .= "drew their swords and shot each other.\n";
$msg .= "A deaf police man heard this noise,\n";
$msg .= "came and killed those two dead boys.\n";
$msg .= "If you don't believe this lie is true,\n";
$msg .= "ask the blind man - he saw it too!\n";

$msg =~ tr/\n//d;
for my $sentence ( split /[.!?]/ , $msg ) {
    if ( $sentence =~ /^\s*([a-zA-Z0-9]+)\s+([a-zA-Z0-9]+)\s+/ ) {
        print "$1 $2\n";
    }
}
__END__
One bright
Back to
A deaf
If you

[download]
Cheers - L~R

In reply to Re: Strip user-defined words with regexp by Limbic~Region
in thread Strip user-defined words with regexp by Marcello

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