One of the most important Verbal aspects to be considered is Lexical Selection.
Of course, there are many other Pragmatic Verbal considerations including:
Maintaining a topic (many kindergarten children start a new topic with almost each new sentence);
Changing a Topic (folks get bored if you have only one topic of interest);
Introducing a topic (its necessary to provide not too much, nor to little information in the process).
In regards to providing enough pre-information, I recall we almost gave my wife's mother a stroke when we broke the news about the birth of Ezmarelda, since we had neglected to mention that my wife was pregnant.
Perhaps, one of the most important Verbal Pragmatic Rules deals with Lexical Selection. I suspect that my wife turned down my first proposal of marriage because of my choice of words.