Here is a good example on teaching the passive voice from esl.about.com:
Passive VoiceIt's important to study the passive voice to place the focus on the object of an action, rather than the person doing that action.
English students should learn how to use the passive voice for explaining processes and for business situations. Here are some examples:
Somebody made my car in Detroit. -> My car was made in Detroit.
Somebody painted this beautiful picture. -> This picture was painted by George Smith.
A number of people in company ZYZ have designed this recorder. -> This recorder was designed by the ZYZ Company
Study the passive voice below and then practice your writing skills by changing active sentences to passive sentences. Teachers can use this lesson plan on recognizing the differences between active and passive sentences.
Passive Voice Grammar
The passive voice is used when focusing on the person or thing affected by an action.
- The Passive is formed: Passive Subject + To Be + Past Particple
The house was built in 1989.
- It is often used in business when the object of the action is more important than those who perform the action.
We have produced over 20 different models in the past two years. Changes to: Over 20 different models have been produced in the past two years.
- If the agent is important (the person, company or thing that does the action) , use "by"
For Example: Tim Wilson wrote "The Flight to Brunnswick" in 1987. Changes to:"The Flight to Brunnswick" was written in 1987 by Tim Wilson.
- Only verbs that take an object can be used in the passive voice.