Phrases and clauses are both groups of words that work together in a sentence. The difference is that a clause has a subject and a verb—often, a clause could be a sentence if it were all by itself, and when it could be, we call it a main clause or an independent clause.
My writing students come from all over the world and write in every genre and subgenre imaginable. While their writing is often solid, sometimes it lacks key elements. This is hardly surprising since there are so many things to juggle in creating a good story . . . see more.