my $r = "Time to work";
s/work/play/;
print $r;

##</code><code>##

my $r = "Time to work";
$_ =~ s/work/play/;
print $r;

##</code><code>##

my $_ = "Time to work";
s/work/play/;
print $_;

##</code><code>##

my $r = "Time to work";
$r =~ s/work/play/;
print $r;