Section A The final step of SQ3R is revision. Revision should not be regarded as something to be undertaken just before examinations.【76】One of the most practical results of memory experiments is that material that has to be retained over long periods should be studied and re-studied. Memories become stronger and stronger with each relearning, and forgetting proceeds more slowly. Common experience suggests that the details of what we learn fade very quickly, often within the first hour or so.【77】Indeed, in listening to an hour’s lecture much of the early part of the lecture may have been forgotten well before the end—so that experienced teachers repeat and recapitulate the important points of their lectures at the end. To prevent the sudden and catastrophic loss which takes place so early, early revision is required. That means going over the lecture or piece of work again as soon as possible afterwards, thinking about it, or discussing it with others or applying the facts and knowledge in some practical exercises.【78】You should certainly go over your notes of lectures, work periods and experiments the very same day—even if it is only for a few minutes. 【79】If you feel that merely going over the work again is too tedious an exercise, jcead another account of the same subject in another textbook, expanding your notes by additions and comments; for this purpose write your notes on one side of the paper only, to leave room for these additions. In revision before examinations you should pay particular attention to the earlier material you have learnt, as more of it will have been forgotten. You should leave yourself time to go over all the material you have covered.【80】Studies have shown that subjective estimates of strengths and weaknesses are often at fault. You are often weak on material which you are confident you know well. Active revision, and a few attempts at answering old examination questions should give you a better idea of where your true strength and weaknesses lie. (46)