Sentences are easy for your readers to understand if it is clear who is doing what. You can write sentences that are easy to read if you follow a few basic principles.

• Express characters in subjects and actions in verbs
  
  In an affirmative or negative sentence
  
  
  • the grammatical subject is the noun (or nouns) before the verb, and
    
    
  • the characters are the nouns that express the concepts, people or things you are writing about.
  
  
  Readers will understand a text more easily if its grammatical subjects are also frequently characters. For example, the following text feels dense for two reasons.
  
  

  Between 1980 and 2005, the evolution of the banking industry observed a significant growth of the savings bank sector but has since then witnessed the virtual disappearance of the savings bank.

  
  Firstly, the grammatical subject of the verb is not a character. The author is writing not about an evolution (the grammatical subject) but about the banking industry and the savings bank sector (the characters of the text). Secondly, the actions done by these characters are expressed in the form of nouns (evolution, growth, disappearance). Most readers will understand the sentence more easily if you make the characters the grammatical subjects of the actions they do.
  
  

  Between 1980 and 2005, the banking industry evolved in such a way that the savings bank sector grew significantly but since then this sector has virtually disappeared.

  
  This process of expressing the action of a sentence in the form of a noun and not in the form of a verb is known as nominalization and, although it can be used to good effect on occasion, it should be avoided when it forces an abstraction that is not a character into subject position.  
  
  

  The separation of the components of a mixture is made with chromatographic techniques and the identification of organic compounds is carried out with spectroscopic techniques.

  
  

  The components of a mixture are separated with chromatographic techniques and organic compounds are identified with spectroscopic techniques.

  
  
  
• Keep the subject short
  
  Readers will understand a sentence more easily if the subject of the verb is short and concrete or a familiar abstraction and if the longer, more complex information comes after the verb.  
  
  

  Novel nutritional technologies and innovative techniques for optimizing yield and increasing profit in a context of increasing production expenses is the subject of the section below.

  
  

  The section below discusses novel nutritional technologies and innovative techniques for optimizing yield and increasing profit in a context of increasing production expenses.

  
  
  
• Keep the subject towards the beginning of the sentence
  
  Position the subject of the main verb towards the beginning of a sentence. Too much information before the subject will overload the reader.
  
  

  Citing the example of a 17-year-old student who was working 35 hours a week in a well-known burger chain restaurant so that he could pay for a new car while simultaneously studying full-time for his university entrance examinations at the local secondary school, Dr Smith urged for greater communication between parents and educational institutions.

  
  

  Urging for greater communication between parents and educational institutions, Dr Smith cited the example of a 17-year-old student who was working 35 hours a week in a well-known burger chain restaurant so that he could pay for a new car while simultaneously studying full-time for his university entrance examinations at the local secondary school.

  
  In the first text above, the subject of the main clause (in bold) is the forty-fifth word. In the second, it is the tenth. Readers find it much easier to understand long pieces of text if they appear after the subject and the verb rather than before them.
  
  
• Maintain the subject-verb-object connection
  
  The essential elements of an English sentence are the subject, the verb and the object. Those sentences that keep these elements together tend to be clearer than those that separate them.  
  
  

  Dr Jan Wilkinson, despite criticism from both within her discipline and without, defended her thesis on notional groups in her next paper.

  
  

  Despite criticism from both within her discipline and without, Dr Jan Wilkinson defended her thesis on notional groups in her next paper.

  
  
  
• Respect end focus
  
  End focus is the principle that the new or most important information in a clause or sentence comes at the end. The following sentence is the last one from a thesis on juice concentration processes.
  
  

  The main conclusions are that low values of retention and permeate flux are the causes of the problems in juice concentration processes.

  
  The information is not in the correct order. Juice concentration is the topic of the research, it is announced in the title (Juice Concentration: Problems and Solutions) and is, therefore, a major character throughout the text, so the final sentence should position it, as a major character, in subject position and then go on to provide some information about it after the main verb. The aim of the sentence is to communicate what problems juice concentration involves, so this information should be placed in the focus position.
  
  

  The main conclusions are that the causes of problems in juice concentration processes are the low values of retention and permeate flux.

  
  Likewise, in the following text the author sets up an expectation in the first sentence – that the number of sensors is important – but then buries the information that responds to this expectation in the middle of the following sentence.
  
  

  The tests showed that not all of the sensors helped to monitor the ripening process. In fact, for purposes of classification, with two sensors best results were achieved.

  
  The principle of end focuses requires a second sentence such as the following.
  
  

  The tests showed that not all of the sensors helped to monitor the ripening process. In fact, for purposes of classification, results were best with just two.