Five W's and the one H

Who
    Romeo, Tybalt, Mercutio, Benvolio
What
    Mercutio and Tybalt fight
        Mercutio dies
    Romeo and Tybalt fight
        Tybalt dies
Where
    A public place   
When
    After the marriage of Romeo and Juliet
Why
    Tybalt sent a letter to Romeo challenging him to a deul
    Tybalt made fun of Romeo and Mercutio
    Mercutio got angry
    Tybalt kills Mercutio
    Romeo is very angry and searches for Tybalt
    Romeo kills Tybalt out of rage
How
    There were two duels (Mercutio and Tybalt, Romeo and Tybalt)