We say things in the active voice when we want to show who or what has done something.
In the active voice the agent (the person or thing that does something) is the subject of the sentence.
For example:
"She cleaned the office." (Who cleaned the office? She did=the subject)
"He crashed into my car." (Who crashed into my car? He did=the subject)
The active voice uses fewer words than the passive voice.
