$x =~ /^Who/m;   # matches, "Who" at start of second line
$x =~ /\AWho/m;  # doesn't match, "Who" is not at start of string
$x =~ /girl$/m;  # matches, "girl" at end of first line
$x =~ /girl\Z/m; # doesn't match, "girl" is not at end of string
$x =~ /Perl\Z/m; # matches, "Perl" is at newline before end
$x =~ /Perl\z/m; # doesn't match, "Perl" is not at end of string