In your course, you have been—or will be—exploring a number of topics: from travel to identity to translation (both cultural and literary). That is, you already have a number of topics from which to choose, but each of these is too large for a focused research assignment.
By grounding these topics in a particular text or even a particular passage from a text, you can narrow your focus enough to sustain a research project. However, the decision to write on a work of literature is rarely this simple. Describing research as the act of choosing a topic and then investigating a text based on that topic misrepresents how literary research unfolds. More often than not, we approach our topics from the opposite perspective: we are captivated, confused, or troubled by a passage and want to answer the questions that arise from those responses. Articulating those questions for ourselves is often the first step in literary research.
Topics, then, are most useful because they reveal a critical dialogue (e.g., about themes of exile and return in literature) in which our questions might find answers. Conversely these critical dialogues can teach us in the first place how to ask good questions about the texts we read.
Questions that occur to us as we read are not yet focused research questions. To move from curiosity to research question we must understand a few things about our project, including (but not limited to):
Wayne C. Booth's classic The Craft of Research offers further discussion of this process and is worth exploring before you begin your research. (However, his conception of research is more linear than I view it.) See, in particular, these chapters:
Even though Booth et al. describe a linear movement from topics to questions to problems, you should keep in mind that research doesn't always move smoothly in this direction. Sometimes research results can reveal—not merely answer/solve—questions or problems. By remembering that research is iterative and recursive—i.e., that you might shuttle back and forth between planning and research—you can feel less intimidated to start your research, understand where your interests intersect with the published literature, and how you might best refine your questions to respond to an existing scholarly dialogue.