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Be sure that your business letter has only one purpose. Everything in your letter should be geared toward getting a particular response. If you have two purposes, you will cut your effectiveness in half.
WRITING STYLE: ACTIVE AND PASSIVE VOICE
As you write more (and read more), you will probably want to become an even better writer. One way to make your writing livelier and more direct is to use active voice. In active voice the subject of the sentence performs
In passive voice the subject is acted upon by some other agent.
A goal was scored by Amy.
A goal was scored.
If the person or thing performing the action is indicated at all, it will be in a prepositional phrase beginning with by. The doer of the action has less importance than in active voice when it is the subject of the sentence. In passive voice the verb will always be at least two words (a form of "to be" plus a past participle). Passive voice, therefore, requires more words than does active voice.