“I can tell by his voice that this man is a Montague.”
There is a long standing rivalry between the montague family and the capulet family fights break out in public on a regular basis.
Tybalt despises Romeo being at the ball and meeting Juliet since he is a montague and they are capulets that are there.
Juliet and Romeo are about to get married. However friar lawrence doesn't think it is good idea because he can be killed by the king for marrying a capulet with a montague.
Oh happy dagger!
Juliet's father is telling her that she has to marry Paris on thursday morning and Juliet doesn't want to since she married Romeo.
Romeo kills himself by drinking a poison because he thinks that Juliet has died. However he didn't know that it was a plan for Juliet to not marry Paris by taking a potion that will make her fall asleep for 24 hours so that she can still be with Romeo.
Juliet wakes up from the potion to see Romeo lying dead on the floor from drinking poison. So Juliet sees if there is any left and drinks the rest. But then see that Romeo has a dagger and she takes it and kills herself.