A participial phrase consists of a participle plus other elements that function as an adjective to modify a noun or pronoun. There are two types of participles: present participles ending in "-ing" and past participles ending in "-ed", "-en", "-d", "-t", or "-n". Participial phrases should be placed next to the words they modify and include those words. They are punctuated with commas when they begin a sentence or contain non-essential information.