He walked down the stairs, his head pounding from last night.Whenever I see a group of words like the words in italics above, which doesn't have a subject or verb (therefore not a clause), I know that it is a phrase. Often the words are set off from the sentence by a comma. I then have to decide what part of speech it is:noun, adverb, preposition or adjective.
In this case, I assume the sentence would not make sense without the comma, correct? The parenthetical information is an adjective phrase, but if the phrase included a finite verb, then it would be a clause and the comma would be ungrammatical (a comma splice): He walked down the stairs. His head was pounding from last night.
So, is this all right to do, omitting the finite verb so that it's not a clause and therefore a comma is allowed? I often see this omittion of a subject or verb so a comma can be used instead of a full stop which reduces flow.
I have always wondered if this is allowed in formal writing, so I would love to know the answer...
Thanks a load!
