A grammatical construction where the subject of a sentence is the receiver of the action.
The cake was baked by her for her friend's birthday.
To shift the focus onto the receiver of the action.
I am going to attend the meeting tomorrow.
The letter was mailed yesterday by my sister.
Subject + helping verb + main verb + object
She has been waiting for the bus for ages.
The author will publish the book next month.
The baby was sleeping peacefully in her crib.
Past simple tense