Breakdown of La victime a été interrogée par l'inspecteur.
être
to be
avoir
to have
par
by, through / out of (motive)
interroger
to interrogate
Questions & Answers about La victime a été interrogée par l'inspecteur.
Why is it a été interrogée instead of just a interrogé?
This is the passive voice in the past tense. If we said La victime a interrogé, it would mean the victim questioned someone else! To say the victim was questioned, we use the verb être in the past tense (a été) followed by the past participle (interrogée).
Why does interrogée have an extra e at the end?
In the passive voice, the past participle always agrees with the subject, just like an adjective. Since la victime is a feminine noun, we add an e to interrogé.
What if the victim was a man? Would it be le victime?
When do we use par to mean 'by'?
In passive sentences like this one, the person doing the action (here, the inspector) is introduced by the preposition par.