How Purpose Affects Topics
Your purpose helps you to narrow a topic, since it demands particular approaches to a general subject. For example, if you're writing about how state policy affects foreign language study in grades K-12 in Oregon, you could have several different purposes. You may need to explain how the Oregon law came about; that is, what influenced it and who was responsible. Or perhaps you would need to explain the law's effects, how curriculum will be altered, etc. Another purpose might be to evaluate the law and to propose changes. Whatever purpose you decide to adopt will determine the questions which give direction to your topic, and (in the case of a research paper) will suggest the type of information you will need to gather in order to address those questions.