Question

She invited him to her house yesterday (change into passive voice)

Answer 1

He was invited to her house yesterday by her.
In an active voice, the doer of the action is followed by the action and then the receiver of the action.  But in the case of passive voice, the receiver of action is followed by the action then finally the doer of action. In the above instance, 'He' was the receiver of action. 'invited' is the action and 'her' is the doer of the action.