Identify the problem in the following sentence

The most compelling and effective messages contain a variety of sentence patterns and avoid common sentence faults. you can create successful messages with sentence variety by understanding the four sentence types, controlling the length of your sentences, and avoiding fragments, run-ons, and comma splices. identify the correct pattern of a complex sentence. an independent clause and a dependent clause one independent clause with a subject and a predicate verb two independent clauses joined by a conjunction, a semicolon, or a conjunctive adverb