Is audience a pronoun, or just a noun? Can "yourself" be a demonstrative or Indefinite pronoun?

No, to both questions.

"audience" is a noun.

"yourself" is a reflexive personal pronoun.

http://grammar.ccc.commnet.edu/grammar/pronouns1.htm

Select the sentrance that has correct pronoun usage.

1. The team of reporter stunned their audience when the result of the election were revealed.
2.
1. The team of reporter stunned its audience when the result of the election were revealed.

The word "audience" is a noun, not a pronoun. It refers to a group of people who gather to watch or listen to something, such as a performance, speech, or presentation.

On the other hand, "yourself" is a reflexive pronoun, which means it reflects back to the subject of the sentence. It is not a demonstrative or indefinite pronoun. For example, in the sentence "You can do it yourself," "yourself" refers back to the subject "you" and emphasizes that you should do the action independently.

To determine the type of pronoun, it is helpful to understand its function in a sentence. Pronouns can be classified into various categories, including personal pronouns, demonstrative pronouns, indefinite pronouns, reflexive pronouns, interrogative pronouns, and relative pronouns. By identifying how a pronoun is being used in a sentence, you can determine its classification.