2. The new recruit received an injury during the first day of training.
In grammar, an active voice is a term used for sentences in which the subject is the one directly performing the action. For example,
Joe killed the snake.
In this sentence, the subject Joe performs the action described by the verb kill.
Active voice pays attention to who performed an action
A contrast to an active voice is a passive voice. In a passive voice, the subject is being acted upon by another object whether the object is defined or not. An example is;
The snake was killed by Joe.
Here, the thing (snake) acted (killed) upon is the subject of the sentence.
Passive voice pays attention to what was acted upon
1. The front door locked and had been broken by the thief.
This is a passive voice because the thing acted upon, which is the front door, is the subject of the sentence.
2. The new recruit received an injury during the first day of training.
This is an active voice because the subject, which is the new recruit, performs the action described by the verb receives.
3. The last piece of pumpkin pie was eaten by someone.
This is a passive voice because the thing acted upon, which is the last piece of pumpkin, is the subject of the sentence.
4. The history exam was rescheduled for next week.
This is a passive voice because the thing acted upon, which is the history exam, is the subject of the sentence.
