How you say something is often as important as what you say. A desire to communicate clearly, vividly, and persuasively with your reader should be evident in your attention to saying things well. A lively, flexible, forthright prose style—neither stilted nor stodgy, but executed with precision—is an engaging prose style. Steer clear of the usual snags in sentence-level execution: vagueness, wordiness, redundancy, faulty diction, the passive voice, indefinite pronouns, mixed tenses, comma problems, and so on. These videos attend to matters of punctuation and parallelism; the exercises the follow highlight other potential sentence problems.