Answer:
Jackson ate lunch early. Simple Past
Jackson has eaten lunch. Present Perfect
Explanation:
Jackson ate lunch early. (Simple Past: Eating lunch has started and ended in the past. Someone might say this when the time for eating lunch has also ended. Lunch happened early, and it is over now.)
Jackson has eaten lunch. (Present Perfect: Jackson started and finished eating lunch in the past, but lunch time is still going on. Someone might say this when others are preparing to eat lunch, and they want to know whether Jackson will join them.) while To form the past perfect tense you use the past tense of the verb "to have," which is had, and add it to the past participle of the main verb. For example: subject + had + past participle = past perfect tense.
Some examples of the past perfect tense can be seen in the following sentences:
Had met: She had met him before the party.
