If you haven't made your own sentences and pictures, then you can download a set of sentences and pictures by
clicking on this link. Choose one member of each active/passive sentence pair, and ask your participant to read
it out. Then show them the following picture and ask them to use a simple sentence to
describe the event in the picture. Note what they say (or record them). There are three things to look out for:
1. participants are generally more likely to use active than passive sentences;
2. they are more likely to use a passive if the 'prime' sentence was a passive;
3. they are more likely to use a passive if the agent (the doer of the action in the picture) is animate (a person or an animal).