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

while (<DATA>) {
if ( $_ =~ s/([?.,]$)/$1/){ print "$_ $1\n" }; 
}

#  puts ?., in a character class [] anchored at the 
# end $, and () captured to $1, a 
# regex internal variable. 
	
__DATA__

4 score and 7 years ago?
our forefathers came,
upon a continent.
foo
bar bazz	
__END__