Past Perfect

AFFIRMATIVE NEGATIVE INTERROGATIVE
Formula Subject + had + verb in past participle / third form Subject + had not (hadn’t) + verb in past participle / third form Verb + had + subject + verb in past participle / third form
Subject of any gender and number The Avengers had defeated Thanos in the past. The Avengers hadn't lost any battles in the past. Had the Avengers defeated Thanos in the past?
Subject of any gender and number Iron Man had built a new suit. Iron Man hadn't revealed his secret suit designs. Had Iron Man built a new suit?