The longer mark questions require you to demonstrate two skills. The first is is an informative description of what is asked (AO1 marks) and/ or analysis and evaluation (AO2 marks). You gain AO1 marks from listing your knowledge and facts - this is where revision is most important as you simply have to know your stuff. For example, if the paper asks you to outline reserch into a field, give the experiments that were conducted including methodology and results. AO2 marks are gained for evaluative skills. You will get these marks for a critique of the methodology, how generalisable the results are as a result of this, conclusions, or supporting studies. Key phrases like "this research suggests that..." or "an issue with this is..." will see you gain good AO2 marks. This is easier said than done becuase the exam paper will not directly tell you which skill they are looking for, so the key is in reading the question carefully. Words or phrases used in the question will tell you if your answer should be descriptive (AO1), analytical (AO2) or both. For example, a question starting with "outline" or "describe" is looking for a descriptive, AO1 answer but one that says "outline and evaluate" or "discuss" is looking for AO2 skills aswell. The question may just require evaluation too (e.g. "evaluate research into..."), in which case you can skip the descriptive aspect and just explain your AO2 points. I would suggest highlighting the key words in the question and planning out your points before you begin writing. Half of the work is done once you know exactly what your marker is looking for, then it's just a matter of putting your revision onto the paper!