Students may not repeat for credit courses that are not listed as repeatable in the Undergraduate Catalog. If you register for non-repeatable courses that you have previously taken, you will earn no credit for those courses and they will not count toward fulfillment of degree requirements.
While some upper-division courses taught by the Department of English are repeatable for credit, many are not. You are responsible for knowing which courses may, and which courses may not, be repeated. You should, therefore, consult the Undergraduate Catalog in order to confirm that courses for which you wish to be registered more than once are, in fact, repeatable.