What do participial phrases start with?

Participial phrases start with a present participle (ending in -ing) or a past participle (usually ending in -ed, -en, or other irregular forms). These phrases include the participle itself along with any modifiers or objects. For example, in the phrase "running quickly," "running" is the present participle, while in "broken vase," "broken" is the past participle. Participial phrases function as adjectives, providing more information about a noun in the sentence.