1. The dog chases the cat. - The cat is chased by the dog.

2. The chef prepares the food. - The food is prepared by the chef.

3. The teacher explains the lesson. - The lesson is explained by the teacher.

4. The doctor examines the patient. - The patient is examined by the doctor.

5. The gardener waters the flowers. - The flowers are watered by the gardener.

6. The singer performs the song. - The song is performed by the singer.

7. The athlete runs the race. - The race is run by the athlete.

8. The company sells the product. - The product is sold by the company.

9. The children play with the toys. - The toys are played with by the children.

10. The workers build the house. - The house is built by the workers.