You are coming to the U.S. as an exchange visitor for a specific objective. Your DS-2019 contains the category which defines your particular activity (non-degree student), a code which indicates your specialized field of study, and a brief description of your activity.
The U.S. State Department expects you to stay with your original objective for coming to the United States. As an exchange visitor, you are normally not allowed to change your category, and you are expected to carry out the activity described in Section 4 of your DS-2019. Please consult your Responsible Officer if you are considering any change in your original program activity.