#!/usr/bin/perl -w

use strict;

while(<>)
{
        if(m/\s*\ \w+ 
        \ (\w+|
        \w+\ \w+|
        \w+\ \w+\ \w+) 
        \ (?=\1)/x)
        {
                $_ =~ s/$1//;
                print;
        }
}