<em>Interesting question. Here are the revised sentences, complete with commas (when they are needed).</em>
<em />
<em>After I finished the Chicago Marathon, my legs were tired.</em>
<em>Muhammed Ali was the greatest athlete ever.</em>
<em>My mom told me to clean my room, wash the dishes, and take out the garbage.</em>
<em>I want to listen to my iPod in class, but my teacher won't let me.</em>
<em>If I had the chance, I would change our mascot to a gorilla.</em>
<em>No, I don't want to go to Taco Bell for lunch.</em>
<em>The fireworks were fun to watch.</em>
<em>Marcus Brutus, who was tricked by Cassius, was the last conspirator to stab Caesar.</em>
<em>Antony, thinking the conspirators would kill him, fled after he saw Caesar's dead body.</em>
