This posting finds examples of the elements in various examples.
As you identify nouns of direct address, imagine a dialogue occurring. For example, these nouns are used to call upon a person or gain his or her attention. "It can be the person's name or the name by which he or she is known. Here are some examples:
Cindy, why are you here? (Noun of direct address is Cindy)
Mom, please help me. (Mom)
I didn't understand, Judge, that I had to tell the truth. (Judge)
Don't you dare leave this room, Kelly! (Kelly) " (www.lessontutor.com/eesnouns.html).
Please refer to http://www.lessontutor.com/eesnouns.html for a brief tutorial.
Next, as you locate appositives, please remember that they are nouns or pronouns -- often with modifiers - "set beside another noun or pronoun to explain or identify it"(http://owl.english.purdue.edu/handouts/grammar/g_appos.html). Please refer to the tutorial at ...
Noun usage is demonstrated.