#!/usr/bin/env perl

use strict;
use warnings;

use Lingua::EN::Inflect 'A';

while (<DATA>) {
    while ( /\b (an? \s (\w+))/gx ) {
        my ( $phrase, $word ) = ( $1, $2 );
        if ( $phrase eq A( $word )) {
            print "RIGHT: $phrase\n";
        }
        else {
            print "WRONG: $phrase\n";
        }
    }
}

__DATA__
I am a howling maniac in an hospital.
It takes a hour to win an honorable mention.
Calling him a umpire is a euphemism.
This is a united front against a evil empire.