If you are covering research, there is a definite answer your research has provided. What was the question? This can be as abstract or concrete as you see fit. It could be the direct questions your paper poses or it could be a question directly stated to the reader, asking them for their thoughts and opinions. Just because you can't come up with an introduction doesn't mean you can't write a skeleton of what you want to say. Cover the main and supporting points; don't worry about detail. This outline will help you realize what it is your paper says. That way, you'll be able to understand what questions you are asking and answering. Using your outline, come up with 2 or 3 questions that your paper touches upon. Seeing as your paper probably has at least 3 points, try to have one question per point. Think of what you are clarifying with your paper. If there is a standard point of view your paper is challenging, your could ask a question of the accepted definition of a word, concept, or societal norm. Choose the question that speaks strongest to your work as a whole. It'll be the one that's easiest to transition from into the bulk of your paper.

Summary:
Think about the point of your paper. Write an outline of your paper. Come up with a short list of questions and choose one.