List of worst grammar issues and online grammar sites

My worst grammar issues involve the use of:

                Then and than

                Accept and except

                Colons and semicolons

                Commas

Places I visited online to help address grammar issues

I don’t use the internet to address my grammar issues.  I use a dictionary for spelling issues.  For punctuation problems I use Quick Study sheets which I purchased and The Little, Brown written by Jane E. Aaron.  I have never used the internet to check my grammar, but I did locate two websites that may be beneficial.

Websites to check grammar:

                Grammarly  http://www.grammarly.com

                Guide to Grammar www.fas.harvard.edu/~wricntr/document