本篇的英文内容来自“Academic Writing for Graduate Students, 3rd Edition by Swales & Feak”（简称AWG）中的第二章‘General-Specific and Specific-General Texts’。
As the name suggests, the structure of General-Specific (GS) texts invloves movement from broader statement to more specific ones. GS texts typically begins with one of the following: a short or extended definition, a generalization or purpose statement, a statement of facts, or some interesting statistics.
Central to creating a GS text is your strategy for information flow. You want to be sure that the text is indeed becoming more specific. Let's look more closely at how this is accomplished in this text on plug-in hybrid electric vehicles.
从一般到具体的过程要注意句子之间的衔接，让读者有路可循。下面这个例子是一篇学术论文的Introduction部分，很好地说明了information flow，也就是各个句子之间的关联，这点在以前的文章On the Logic and Structure of Text中也有说明。
The increasing popularity of Electric Vehicles (EVs) and Plug-in Hybrid Electric Vehicles (PHEVs) is contributed to the savings in fuel costs compared to conventional Internal Combustion Engine vehicles. EVs and PHEVs save energy due to the employment of reverse regenerating braking during the deceleration cycle. This energy is typically stored in batteries and Ultra-Capacitors (UCs). The incorporation of onboard Energy Storage Systems (ESS) and generation in PHEVs has been facilitated and dictated by the market demands for enhanced performance and range. (Amjadi and Williamson, 2009, IEEE Transactions on Industrial Electronics)
This text is a good example of old-to-new information flow. In Sentences 1 and 2 the old information is electric vehicles. Sentences 2 also introduces energy as some new and more specific information. Energy is then picked up in Sentence 3 as old information, and the sentence introduces Ultra-Capacitors as new information. Ultra-Capacitors marks a clear narrowing of the topic, which in Sentences 4 now focuses on on-board energy storage and generation. In just a few sentences, the topic narrowed from the broad focus on electric vehicles to energy storage as well as performance and range of electric vehicles. This has been accomlished by strategically picking up some new information on the new topic.
As in many GS texts, the above example began with a general statement. General statements of facts or tendency can often be useful starting points of papers or sentions of paper. Other common ways to begin a paper include providing some interesting statistics, a quotation, or a definition.
- The verb name itself is uncommon and seems restricted to a focus on the name itself.
This new species was named Ascohyta mycoparastitica.
- The verb denote is common but seems largely restricted to matters of notation.
Any rotational velocity is usually denoted by f.
- The phrase known as is fairly common, according to Google Scholar.
Another principle source of heat is the natural increase in temperature as the depth increases. This is known as the geothermal gradient.
- The verb define is widely used and often represents a safe option.
For the purpose of this study, fast food is defined as food sold be a fanchised restaurant chain offering both dinning and take-out facilities with no 'table' service.
- Finally, the verb refer to is widely used in definition in academic writing.
The natural gas contained in coal formation is generally referred to as coal bed methane.