An absolute phrase, which modifies the whole sentence, usually consists of a noun followed by a participle or participial phrase. Absolute phrases may appear at the beginning or at the end of a sentence. Wherever they appear, they should be set off with commas.
Do not insert a comma between the noun and the participle in an absolute construction.
Style note: Absolute phrases
Exercises:
Major uses of the comma 1
Major uses of the comma 2
All uses of the comma
Related topic:
Participial phrases