Passive past perfect word order

had + been + past participle (3rd form)

Examples: Passive past perfect

Electric cars had been invented.

English passive past perfect

Passive Voice with free online passive past perfect - word order, passive rules and passive voice examples.

Online exercises English grammar and courses.
Free tutorial to English active and passive voice. So don't hesitate to learn the difference between active voice and passive voice in writing with the English Grammar index active voice and passive voice.