I find the best way to know what verbs mean is to pretend for a moment you're not at school, you're perhaps just at home and you get asked to, for example, discuss something. That sort of thing. Then you apply what that means to the question at hand. Discuss is generally just talk about something and then come to a conclusion. For example if in economics you get the question,' Discuss the effectiveness of government policies in achieving economic objectives', you think for a moment what if you got asked to discuss something, then you know what it means and you apply it to the question. And the question is asking you to talk about how effectiveness the policies of the government have been in achieving economic objectives such as economic growth, stable inflation, low unemployment, external stability etc.