well you dont have any options here, but basically throughout the play juliet grows into a stronger and more outspoken girl.
at first she was ready to marry paris and obey her father's commands, now she's found love and has decided to live for herself and marry romeo or at least try to.
then towards the end we see how this once shy and cautious girl is ready to drink poison and fall into a comatose state of near death in order to defy her father and run away with the killer of her cousin tybalt. then at the very last scene we see that she has become a woman ruled by her own desires and refuses to marry anyone but the man she loves, thus following him into death with that whole 'oh happy dagger' bit.