In this sentence “The topic of ? conversation and the characteristics of the social setting are also highly relevent.” I am so confused because it is said in the grammer book that definite articles can be omitted in the following situations:

  • Names of languages and nationalities: Chinese, English, Spanish, Russian (unless you are referring to the population of the nation: "The Spanish are known for their warm hospitality.")
  • Names of sports: volleyball, hockey, baseball
  • Names of academic subjects: mathematics, biology, history, computer science
  • Then why there is no "the" prior to "conversation" ? And what is the usage of "the" in "the characteristics of the social "? To refer something that is unique?? Thanks everyone! I am really really confused!
Conversation can be and is used as an uncountable noun in your sentence. Another example:

We need a little less conversation.

The article is needed in the characteristics of because of the of: The name of if this street is Piccadilly.

A specific setting is assumed in the social setting.

Thanks man.