I often teach punctuation to my law students by asking them to imagine me arguing a case in court. My evidence is solid, I tell them. My analysis is sound. I speak fluidly and persuasively. The only problem: I'm wearing bright orange running shoes. I then ask the students to write down some words that they think might be going through the judge's head as my orange shoes and I make our case. To make the exercise more concrete, I'll actually wear a pair of orange running shoes to class to go along with my otherwise normal business attire of a suit and tie. Sometimes I'll even jump up on the table. The response from students is always the same. "You look ridiculous, your shoes are distracting. I can't take you seriously." Nobody thinks I look professional. I then put on the board the following sentence taken from a brief written by a student working on an employment law case. "The record never established what exactly the employer's reporting requirements are, therefore it is impossible to say objectively whether or not Ms. Lynn has violated them." Unfortunately, not everyone notices that this sentence, like my orange shoes, also looks ridiculous, is distracting, and makes it hard to take the person who wrote it seriously, at least if you know how punctuation in English generally works. The culprit is the comma. Commas are generally not strong enough to hold together what are essentially two separate sentences. But if you didn't know that, or if you think, as the student perhaps did, "Well, if I throw in a 'therefore,' I'll be okay," then you're going to look pretty foolish, not just in that sentence, but in a lot of other things you write as well. It's hard to fix mistakes you don't see. I'm of course not really worried about my students wearing orange running shoes to court or some other place where that footwear is not appropriate. They all have mirrors, they can all notice or at least have someone tell them when they're outfit might damage their credibility. But what they don't have or at least could always use help better developing are mirrors for their writing. Some way to evaluate if what they're sending out into the world is sufficiently professional and polished. So that is what we will use these punctuation and professionalism segments to do. We'll give you the vocabulary to recognize when you're writing looks like it's wearing orange shoes. We'll start in the next video with the term for the main error in the sentence from the employment law case. Comma splice.