When discussing events that occurred before another past event, the past perfect tense is typically used. The past perfect tense is formed by using “had” followed by the past participle of the main verb.

For example:

“She had finished her work before she went to the meeting.”

“By the time they arrived, the concert had already started.”

In these sentences, the past perfect tense is used to indicate that an action was completed before another action or event in the past. It helps to establish a clear sequence of events and show which action occurred first.