Passive: The ball was thrown by the player.

Most teacher prefer that you write in active voice because you are saying want you want to say in the most concise and efficient way possible. Passive voice makes a writer sound a bit too wordy most of the time; however, there are some cases where passive voice is necessary.

For example, when you don’t know the doer of the sentence. Let’s say you didn’t know who threw the ball. The sentence would read, “The ball was thrown.” If you don’t know the doer, it makes it difficult to write in active voice.

Another example is if you want to write passively for emphasis. Let’s say you are answering the question, “What was thrown?” In this case, you want to write in passive voice to show emphasis on the object, the ball.

Hope this helps.