Which tense is used for action completed in the past

- Which tense is used to express an action completed in the immediate past
- Which tense is used to express a completed action in the past
- Which tense is used to describe a completed action in the past without a specific time reference
- Which tense is used to describe a completed action in the past with a specific time reference
- Which tense is used for an action that was completed before another action in the past