| Exemplary Prose: |
| Essential Writing Skills in Context |
Use
commas to show apposition; avoid using appositive phrases to split
adverb/adjective descriptors.
Nouns as appositives
A word or group of words is set off by commas when the word or group of words - commonly called an appositive - adds meaning to the main idea and yet is not crucial to the basic meaning. (It could be deleted and the sentence would still make sense.)
noun
appositive
Bobby, Barry’s father, was an excellent baseball player.
The noun Bobby and the noun phrase Barry’s
father refer to the same person. In fact, this sentence is a shortened
version of another sentence:
Bobby, who is Barry’s father, was an excellent baseball player.
However, when the word or group of words is needed to
convey the intended meaning, then that word or group of words is not set off by
commas.
Barry's father Bobby was an excellent baseball player.
An easy rule of thumb, although not 100 percent accurate, which is typical in the English language, is as follows:
CAPITALIZED NOUN = common noun = commas
common noun + CAPITALIZED NOUN = no commas
Appositives differ from subject complements and object
complements in that appositives can be turned into clauses beginning “who or
which is (or are).” An appositive is usually set off from the rest of the
sentence by commas, as in the example above. Sometimes, however, a dash or a
pair of dashes is used instead, as in this sentence:
My favorite comedians are the Three Stooges – Curly, Moe,
and Larry.
When an appositive provides only additional information and is not needed to identify the first noun, it must be marked off from the rest of the sentence either by commas or by dashes. However, sometimes the first noun is unclear without an appositive to help identify the person or thing referred to:
My sister Doreen is the teacher.
The noun Doreen is an appositive because it helps to identify “My sister” (“My sister who is Doreen”). It is not marked off by commas because without it, it might be impossible to say which of the speaker’s sisters is meant.