You should post your program. Take care of "modifiers" (http://perldoc.perl.org/perlre.html#Modifiers) : 
while (<DATA>) {
    /([A-Z]+)/i;  # upper AND lower!
    print $1,"\n";
}

[download]
output : 
ABU
individual
AFGHAN
AYAT
a
Pushtoon
Sabaqah

In reply to Re^3: Fine tuning a reg exp (\w) by brx
in thread Fine tuning a reg exp by markjrouse

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