Answer: C) Had forgotten.
Explanation for this question is being written.
Answer: D) Had left.
Answer: B) Had studied.
Answer: B) Had finished.
Answer: B) Had stolen.
Answer: D) He had eaten lunch at 12 o'clock.
Answer: A) Had been invented.
Answer: A) Had made/ started.
Answer: B) He had finished before I arrived.
Answer: B) Had
Answer: A) Had walked.
Answer: D) No option is correct.
Answer: A) Had eaten.
Answer: D) Had found.
Answer: A) Had won.
Answer: B) They had finished the project.
Answer: A) Had left.
Answer: A) A hadn't finished.
Answer: C) Had seen.
Answer: A) Had addressed.
Answer: A) Had discussed, got.
Answer: C) Had cleaned.
Answer: A) Had
Answer: C) She had already left when I arrived.
Answer: A) We had cleaned the house before my mom came back.
Answer: B) Had already left.
Answer: A) Had flown.
Answer: A) Had gotten.
Answer: A) Had finished.
Answer: A) Had lost.
Answer: B) Had composed.
Answer: A) Had made.
Answer: C) Had trained.
Answer: D) Had been.
Answer: A) Had + past participle.
Answer: B) Had found.
Answer: B) Had already escaped.
Answer: A) Had met.
Answer: B) Had started.
Answer: D) Had read.
Answer: A) Had been stolen.
Answer: A) Had heard.
Answer: A) They had played soccer before it rained.
Answer: C) El pluscuamperfecto.
Answer: A) Past perfect.
Answer: A) Had arrived.
Answer: B) The team lost because they hadn't practiced enough.
Answer: A) Had built.
Answer: B) Realized
Answer: A) Had chosen.
Answer: C) Had protected.
Answer: C) Had left.
Answer: A) Stood/had waited.