You need either a bigger body, which is the middle area with your claims and supporting evidence, or a bigger thesis paragraph, which are all of your claims in general, or what you're trying to prove. I recommend using Google for examples or pointers.
Mercutio wants to protect Romeo, and hesitates while Romeo tries to get himself and Tybalt to stop fighting. Tybalt uses it as an opportunity to kill Mercutio. Romeo chases down Tybalt in rage and kills him.
