Modifier

Definition

Modifiers are words, phrases, or clauses that provide description in sentences. Modifiers allow writers to take the picture that they have in their heads and transfer it accurately to the heads of their readers. Essentially, modifiers breathe life into sentences.

Modifiers that appear before the head are called premodifiers. Modifiers that appear after the head are called postmodifiers.

Modifiers can be adjectives, adjective clauses, adverbs, adverb clauses, absolute phrases, infinitive phrases, participle phrases, and prepositional phrases. The sentence above contains at least one example of each:

Adjective = poor.
Adjective clause = who just wanted a quick meal.
Adverb = quickly.
Adverb clause = as a tarantula wiggled out of his cheese omelet.
Absolute phrase = a sight requiring a year of therapy before Stephen could eat eggs again.
Infinitive phrase = to get through his three-hour biology lab.
Participle phrase = gagging with disgust.
Prepositional phrase = on the cafeteria tray.

Without modifiers, sentences would be no fun to read. Carefully chosen, well-placed modifiers allow you to depict situations with as much accuracy as words will allow.

Examples :

• "Louis, I think this is the beginning of a beautiful friendship."
• "I'm an excellent housekeeper. Every time I get a divorce, I keep the house."
• "Sometimes when we are generous in small, barely detectable ways it can change someone else's life forever."
• "I met a girl who sang the blues
  and I asked her for some happy news,
  but she just smiled and turned away.
  And the three men I admire most,
  The Father, Son, and the Holy Ghost,
  They caught the last train to the coast
  The day the music died."
• "They scream your name at night in the street
  Your graduation gown lies in rags at their feet
  And in the lonely cool before dawn
  You hear their engines roaring on
  But when you get to the porch they're gone
  On the wind, so Mary climb in
  It's a town full of losers
  And I'm pulling out of here to win."

source : http://grammar.about.com/od/mo/g/modterm.htm
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