Close reading means you read a passage or text carefully, this allows the reader to interpret, understand and remember the text in a deeper way, as the reader focuses on every word, the way these are organized, the way sentences are constructed, among others. This implies close reading is related to focusing on the details and doing an attentive reading to understand the meaning of the text. In this way, if your goal is to understand and remember a text close reading is the best method, as it allows the reader to understand all the details in it and thus get to the main and secondary ideas and remember them easily.
