One of my biggest problems in my writing is my inconsistent and more often than not incorrect use of appositives and descriptive phrases inserted into a sentence. What I don't know is how one determines if they should be separated by commas or dashes or...some form of punctuation that up until this point I did not even know existed. My grammar in general is fairly good, but I'm never sure if I've got this one right. Anyone care to instruct me? Many thanks.