1. An Attributive clause can either be restrictive or nonrestrictive

2. An Appositive phrase can be either essential (restrictive) or nonessential (nonrestrictive)

3. The actual name for a commenting Appositive is a nonessential Appositive or a nonrestrictive Appositive

4. There are two kinds of Appositive phrases: Essential Appositive phrases (also called restrictive Appositive phrases) and non-essential Appositive phrases (also called nonrestrictive Appositive phrases).

5. The word "Appositive" comes from the Latin for "to put near." Nonrestrictive Appositives are usually set off by commas, parentheses, or dashes.

6. Commas set off parenthetical elements such as an appositive, which is a noun phrase or clause that renames or describes the noun directly beside it, and nonrestrictive relative clauses:

7. A complete Atrioventricular septal defect (see figure Atrioventricular septal defect) consists of a large ostium primum atrial septal defect (ASD) in the anteroinferior aspect of the septum, a nonrestrictive inlet ventricular septal defect, and a common AV valve orifice