When your reading an essay or assignment, you can determine the relative importance of the ideas expressed in material by highlighting the key points and paying special attention to the topic sentence in the case of the essay.
It is helpful to use a highlighter in order to emphasize and put special focus on the main ideas of the essay or assignment. In that way, it is easier to understand the texts and to identify the most important details. Furthermore, reading the topic sentence of an essay several times is useful to identify which are the parts in the body of the essay that are directly connected to that sentence and; therefore, which parts are the ones that present the key points of the text since the author always states the main point he/she tries to make about a specific subject in the topic sentence.