you are what you present, you are what you show. what else is there?

non-content problems

1- loose sheets, unstapled.
2- the written assignment presented front-and-back (as if you'll save the planet with this assignment).
3- list of work cited in the same page of the discussion (as if one more page is a sin).
4- MLA conventions not followed with in-text citations and at the end of the draft (remember, no URLs allowed!)
5- ink marks (on the presented assignment),
6- no time of class (i.e., "MWF 10am"),
7- drafts without titles.

content problems (definitely more important)

1- too much copy-and-paste (I call it C/P ratio, people call it plagiarism).
2- syntax problems (broken sentences, hanging phrases, rambling sentences).
3- colloquialisms left and right,  
4- hyperbole (when you exaggerate a point)
5- ad hominem, circularity (remember fallacies?)
6- Paragraphs without the proper thesis or counter identification (as  in "same-sex marriage advocates" vs. "same-sex marriage critics"),
7- coherence problems: broken threads, disconnected points in a same paragraph, etc (the problem here is lack f research and excessive copy-and-paste  without revision)

once finished, read your discussions to point to structural deficiencies in your arguments.

follow these suggestions:

1- prioritize your args. hone them, make them better. read your sentences. make them good with explanatory power.  
2- read your drafts out loud! 
3- redink your own weak points and fix them. build the best possible paragraphs you can build.
4- talk from your heart. digest your appropriated content (so it doesn't look carelessly plagiarized).