When do we usually use the passive form?
When it's not said, known or important who does the action.
If we want to mention who/what did the action which preposition do we use?
by. e.g. The town was over-run by zombies.
The dog chased the cat.
The cat was chased by the dog. The cat is the direct object.
The teacher corrected the student's paper.
The student's paper was corrected by the teacher. The student's paper is the direct object.
The chef cooked the meal.
The meal was cooked by the chef. The meal is the direct object.
The doctor examined the patient.
The patient was examined by the doctor. The patient is the direct object.
The painter painted the portrait.
The portrait was painted by the painter. The portrait is the direct object.
The teacher gave the students a quiz.
The students were given a quiz by the teacher. The students are the indirect object.
The company offered the employees a bonus.
The employees were offered a bonus by the company. The employees are the indirect object.
The chef served the guests a delicious meal.
A delicious meal was served to the guests by the chef. The guests are the indirect object.
The manager sent the employees an email.
An email was sent to the employees by the manager. The employees are the indirect object.
