Nominative absolute

The nominative absolute is a grammatical construction that consists of a noun or pronoun in the nominative case along with a participle or a participial phrase. This construction is typically used to provide additional context or background information to a sentence, and it is often set off by commas. In English, the nominative absolute can add information about time, cause, condition, or circumstance, and it often functions similarly to clauses that start with "when," "because," or "although.