my @array = qw( wilma fred barney betty );

foreach my $i ( 0 .. $#array ) {
    print "$array[ $i ] is the current element.\t";
    print "The next element is ";

    # Before using the next element, test for its existence.
    print
        exists $array[ $i + 1 ]
            ? $array[ $i + 1 ]
            : "unprintable"
                ;
    print ".\n";

    # An approach more to your liking might be:
    #     if ( exists $array[ $i + 1 ] ) {
    # or:
    #     last if $i == $#array;
    # or:
    #     print $array[ $i + 1 ] unless $i == $#array;
    #
}