I have seen some D2L issues with regard to all text on a given page loading properly. I suggest that you immediately use your F5 key and refresh this page now, and each subsequent time you view it.
Below are several links that will lead to grammar handouts on the web.
I strongly suggest that you engage all the handouts, for I expect students to turn in work that does not contain sentence fragments, run-on sentences, and other sentence level errors. For example, if I note that your paper has sentence fragments, then go to the handouts on sentence fragments, so that you can learn how to solve the problem.
Moreover, all of these problems stem from a fundamental inability to distinguish independent clauses from dependent clauses, so students should begin with that particular handout.
Independent and Dependent Clauses (definitions)