Academic style in English is reader-oriented. This can be quite different than other styles of academic writing. In many continental European academic writing styles, for example, the key points tend to be more hidden than in academic English.
In part because of this reader orientation, clear structure is very important in academic English writing. The convention is to clearly indicate the structure and key points of a text using signpost language and topic sentences. This does not mean that the content is simplified, only that it is easier for the reader to find the key points. I suspect that modern academic English has been influenced by the English style used in business and international organisations such as the UN and the EU, since these styles are very reader-oriented.
It is worth emphasising that this is a convention used at the highest levels since continental European writers often feel that the use of signpost language and topic sentences to clearly structure academic texts seems too simplistic. Czech writers who write for British publications, for example, learn to structure their writing in this way. To illustrate this a text from the Oxford Review of Economic Policy has been deliberately chosen for the second post on this topic, Creating a clear structure 2.
Use of signpost language
Signpost language structures the text and guides the reader through it, and should be used throughout the text.
Examples of signpost language are:
This paper argues that, first, second, third, to conclude
An excellent list of signpost language and other generic language for academic writing can be found in the Manchester Academic Phrasebank.
The text in the post Creating a clear structure 2 contains examples of signpost language.
Topic sentences
A topic sentence gives the main idea of the paragraph. In English, it is generally the first sentence. The sentences that follow the topic sentence provide more details about the topic, for example, evidence and examples. This paragraph itself and the one below illustrate the use of a topic sentence followed by supporting information.
Topic sentences are also very helpful for reading in English and can save time in some reading tasks. First, they can simplify finding specific information, for example when doing research. Second, a quick grasp of the overall argument and main points of an essay can usually be achieved by just reading the introduction, the first sentence of each body paragraph and the conclusion. This can also be useful preparation before reading the text in full as it can facilitate understanding. These methods are very useful for both academics and students.
The example text in the post Creating a clear structure 2 also shows topic sentences in use.