#!/usr/bin/perl

while(<DATA>) {
        chomp;
        if( /\A[\w]{3}_\w+_ear\Z/ ) {  
                print "$_ matches \n";
        }
        else {
                print "no joy for $_ \n";
        }
}

__DATA__
ab_wehave_noear
abc_test_ear
abc_test_two_ear
abcc_test_ear


##</code><code>##

no joy for ab_wehave_noear
abc_test_ear matches
abc_test_two_ear matches
no joy for abcc_test_ear