Answer: syntax and diction that are appropriate to the topic and audience
Step-by-step explanation:
In formal discussion, the subject matter is discussed in such a way that it follows a certain method or procedure. This is why the syntax used and the diction have to be appropriate for the topic discussed and the audience involved so that the relevant procedure is followed.
It is therefore important to carry out research on the type of audience one will be in front off as well as the procedures involved so that the proper etiquette is followed.