Verbs can be used in different ways; these are often called ‘voices’. Verbs can either be in the active or passive voice.
E.g Jenny swung the bat. ACTIVE
The bat was swung by Jenny. PASSIVE
Can you see the difference?
In this example, Jenny is the subject as she is doing the action of swinging the bat.
The active voice is used more commonly, but the passive voice is used to focus on what happened, rather than on who is doing the something. It is more formal and impersonal.
Examples in action