I have always had an issue with grammar, no matter how well I had written my paper, there was always a comma missing or a misspelled word (and I assure you there are plenty of mistakes in my other posts). Every writer has some weakeness, but were not here to talk about shortcomings, this time it’s all about the infamous rules of writting. My knowledge of this subject is limited, I know the errors when I see them but I have never been able to memorise the rules. So here are some tools to help you improve your grammar!
http://www.grammarly.com/handbook/
http://www.edufind.com/english/grammar/grammar_topics.php
https://owl.english.purdue.edu/owl/section/1/5/