Use word boundaries (\b).

$_ ='The,quick,brown;foxy.  Does a lot,of:jumping!';

my @words = split(/\W*\s+\W*/, $_); # split into words

print 'Number of words: '.@words."\n";
[download]

gives 4 words. However

my @words = split(/\b\W*/, $_); # split into words
[download]

gives 9 words.