Explain the questions and hypotheses that the researchers were trying to evaluate. What did they know going into the study, and what did they want to learn? If they had a specific hypothesis (or hypotheses), you should be able to explain what it was, and why they made that prediction.
Discuss how they conducted the study. Who were their participants? What variables were they focusing on, and how were these variables measured? The reader should have a pretty good idea what would have happened had they participated in the study.
State the results that were obtained, and then discuss them: what do they mean, and how do these findings relate to the initial ideas the researchers had–their research questions and hypotheses?