print "$_: ", /^\w+$/ && !/^\d+$/ ? 'Good' : 'Bad' for qw[ abc a1c 1b3 123 ];;
abc:  Good
a1c:  Good
1b3:  Good
123:  Bad

##</code><code>##

print "$_: ", /^(?=.*[a-zA-z])\w+$/ ? 'Good' : 'Bad' for qw[ abc a1c 1b3 123 ];;
abc:  Good
a1c:  Good
1b3:  Good
123:  Bad