Choose one of the following National Academy of Engineering Grand Challenges:
Once you've chosen a topic, state it as a question. For example, instead of "transportation systems," you might ask "How do we prevent the improper and unauthorized use of transportation systems, and reduce our vulnerability to their disruption, without seriously restricting mobility or violating individual rights?" Form your research as a question for a problem you want to solve.
Next, identify the main concepts and keywords in your question, and come up with alternative ways to express those concepts. Ask yourself which words in your research topic are most important, and spend a few minutes thinking about alternative ways to phrase them. In our example, the most important keywords/phrases are "transportation systems," "unauthorized use," and "restricting mobility." You may consider replacing "transportation systems" with "mass transit."