Active Voice
Active voice is a grammatical construction in which the subject of a sentence performs the action. It emphasizes the doer of the action.For example; “The cook prepared the food.”. The cook is the subject of the sentence and the doer of action.
Passive Voice
Passive voice is a grammatical construction in which the subject of a sentence receives the action. It emphasizes the recipient of the action or the result, rather than the doer. For example; ” The food was prepared by the cook.” (The object of the active voice sentence becomes the subject of the passive voice sentence.)
Here is a mixed tenses quiz where you will change active to passive voice. You can find the solution as you finish the exercise.