Who is the speaker? Where is it from. Who is the star?
In the sentence that goes "The old brick house that sits on top of the hill was built during the Civil War", the adjective clause would be "that sits on top of the hill".
Adjective clauses function as adjectives to the subject which gives more detail on what the sentence is talking about. Sometimes it can be found in the beginning, or in the end of the sentence, but usually is it found in the middle of the subject and the predicate which is more convenient for writers and readers. In this case, the identified adjective clause which is "that sits on top of the hill" talks more about the old brick house and answers the question which one.
If talking about "I am Nujood" it could be said that the protagonist is a child. His full name is <span>Nujood Mohammed Ali. </span>He is only 9 years old and he is already married. He got married against his will. At the age of 10, he was divorced. As regards nationality, it could be said that he was born in Khardji, Yemen.