Some useful Purdue OWL links

On sentence fragments: http://owl.english.purdue.edu/owl/resource/620/01/

On comma use: http://owl.english.purdue.edu/owl/resource/598/01/

On independent/dependent clauses: http://owl.english.purdue.edu/owl/resource/598/01/

On run-ons and comma splices: http://owl.english.purdue.edu/owl/resource/598/02/