#this file shows variable declaration

$bio_str = "is a biologist and is smart";

print "sarah ".$bio_str;
print "\n";
print "bonnie ".$bio_str;
print "\n";

$bio_str = $bio_str . "and many more";

print "sarah ".$bio_str;
print "\n";
print "bonnie ".$bio_str;
print "\n";