Have you been told, perhaps by your computerised grammar checker, that too many of your sentences are passive? Have you heard the rule of thumb that at least 80 percent of the sentences in any passage should be active? If you've had the problem or heard the rule, and wonder what the terms active and passive mean, and why one is good and the other frowned on, this article is for you.

What makes a sentence active or passive is the relationship between the verb and the subject of the sentence. When a sentence is written in the active voice, the subject performs the action. When the sentence is written in the passive voice, the subject is acted upon.

For example: The man beat the dog. The man is the subject and he's performing the action - is the beater. Compare this with The dog was beaten by the man. In this sentence, the dog is the subject. He isn't doing anything. He is having an action performed on him - he is the beaten. (Note: The dog submitted to a beating expresses the same idea with the dog as the subject, but in the active voice. The verb is "submitted", and it's the dog that's performing this action.)

So to tell whether a sentence is active or passive, ask yourself: "Who or what is the subject, and is the subject actively performing an action, or passively having one happen to him or her?"

Active sentence forms are stronger, shorter, easier to read and more effective in getting your message across.

Look at these examples:

Room reservations should be made by the attendees, or

Attendees should reserve rooms

or even (depending on the context)

Make a room reservation.

Which of these versions sounds best to you?

However, use the passive form if:

• The person or thing that is on the receiving end of the action is more important in the context than the person or the thing performing the action; for example, President Kennedy was killed by a lone gunman.
  
• You don't know who performed the action. My window was broken while I was out last night.