"Romeo, away, be gone! The citizens are up, and Tybalt slain (III.i.125-126)"
In this scene, the Capulets are coming up to Benvolio and Mercutio. This is when Romeo arrives and Tybalt tells him to turn and draw. Mercutio then draws his sword and asks Tybalt to walk.
After Mercutio asks Tybalt to walk, they begin fighting. Romeo decides to stand in front of Mecutio. Tybalt then reaches under Romeo's arms, and stabs Mercutio.
Theme: Love is destructive
"Tybalt, the reason that I have to love thee doth much excuse the appertaining rage to such a greeting. Villain am I none.Therefore farewell. I see thou knowest me not (III.i.63-66)"
In this scene Romeo is angry about the death of Mercutio. After Benvolio comes back and gives Romeo the news, him and Tybalt begin fighting. Romeo then slains Tybalt, this is when the citizens arrive.
What Mercutio says is a pun. Grave could mean that he is serious, or that he will literally be in a grave, as in one in the ground. This helps the audience see that Mercutio, even though he is hurt, still makes a pun.
"Ask for me tomorrow, and you shall find me a grave man (III.i.101-102)"
Romeo refuses to fight Tybalt. Romeo has just married Juliet, and Tybalt is her cousin, so he does not want to fight him. The theme of love is destructive happens here because in the end, they end up fighting so Tybalt and Mercutio die.
"Boy, this shall not excuse the injuries that thou hast done me. Therefore turn and draw (III.i.67-68)"