In short, try to paint your research question in broad brushes and at the same time bring out its significance.
The introduction typically begins with a general statement of the problem area, with a focus on a specific research problem, to be followed by the rational or justification for the proposed study.
Most students and beginning researchers do not fully understand what a research proposal means, nor do they understand its importance.
To put it bluntly, one's research is only as a good as one's proposal.
Make use of subheadings to bring order and coherence to your review.
For example, having established the importance of your research area and its current state of development, you may devote several subsections on related issues as: theoretical models, measuring instruments, cross-cultural and gender differences, etc.
Regardless of your research area and the methodology you choose, all research proposals must address the following questions: What you plan to accomplish, why you want to do it and how you are going to do it.
The proposal should have sufficient information to convince your readers that you have an important research idea, that you have a good grasp of the relevant literature and the major issues, and that your methodology is sound.
A research proposal is intended to convince others that you have a worthwhile research project and that you have the competence and the work-plan to complete it.
Generally, a research proposal should contain all the key elements involved in the research process and include sufficient information for the readers to evaluate the proposed study.