论文各部分内容的作用不同，它们各司其职，从不同角度呈现研究。但同时，又有不少概念让作者们感觉困惑，比如：Abstract
和 Introduction 有何区别？figure captions，labels 以及 legends
是同一个概念吗？在这个系列中，意得辑作者 Fatima 就论文中常见的易混淆概念进行详细辨析。
第四期：study background 和 literature review
The study background and the literature review talk about the existing knowledge in a research area and help identify the gaps that need to be addressed. However, there are significant distinctions between them. The study background is the first part of the Introduction section, which introduces the research topic and sets the context of your research. It is usually followed by the literature review*, which provides a critical analysis of the literature on your research topic.研究背景（study background）和文献综述（literature review）都利用现有信息去锁定有待解决的问题，但又不完全一样。研究背景放在引言开头，用来阐述研究主题，介绍背景。文献综述通常跟在研究背景之后，对研究领域内的文献进行综合分析。The background of a study is written to state the significance of your research while the literature review is written to evaluate the progress of knowledge in your research area. While the study background is written in a short and concise manner, the literature review is relatively detailed, although it should be focused on only that literature that is needed to provide context and motivation for your research question. Both of them eventually lead readers to gaps in research that have remained unaddressed. We can say that the background broadly introduces the topic of your research while the literature review tracks the existing knowledge in the field and helps identify the exact gaps in research that your study will address.研究背景强调的是你自己的研究，而文献综述关注研究所在领域的综合情况。研究背景讲究短而精，文献综述就详尽得多，写作时要学会筛选和你研究最相关的文献。两者都能引导读者发现有待解决的研究问题。总的来说，研究背景负责介绍研究主题，文献综述负责捋清知识结构，找出悬而未决的问题。