#!/usr/bin/perl
use warnings;
use strict;

my $first_line = <DATA>;
my $important = (split ' ', $first_line)[0];

while (<DATA>) { # Process the remaining lines.
    my $value = (split)[0];
    print if $value eq $important;
}

__DATA__
john chevrolet usa
hans bmw       germany
ivan lada      russia
john talbot    uk