c:\@Work\Perl\monks>perl -wMstrict -le
"$_ = 'Three, Four, One, Two';
 ;;
 /([A-Z][a-z][.][\b])/;
 print qq{'$1'  '$2'  '$3'  '$4'};
 ;;
 /([A-Z] [a-z]+ (?: , | \b))/x;
 print qq{'$1'  '$2'  '$3'  '$4'};
"
Use of uninitialized value $1 in concatenation (.) or string at -e line 1.
Use of uninitialized value $2 in concatenation (.) or string at -e line 1.
Use of uninitialized value $3 in concatenation (.) or string at -e line 1.
Use of uninitialized value $4 in concatenation (.) or string at -e line 1.
''  ''  ''  ''
Use of uninitialized value $2 in concatenation (.) or string at -e line 1.
Use of uninitialized value $3 in concatenation (.) or string at -e line 1.
Use of uninitialized value $4 in concatenation (.) or string at -e line 1.
'Three,'  ''  ''  ''