In the play "Romeo and Juliet" by William Shakespeare, the author gives Juliet a challenging task in answering her mother's grief-stricken speeches. Here, Juliet has to think on her feet, act quickly and speak in a duplicitous way. The task is made even more difficult,almost impossible, because the grief she describes about her cousin is probably genuine - she probably did love him too as her kith and kin. So poor Juliet is torn four ways. Her quick-thinking and eloquent speech shows remarkable resourcefulness and a swift intelligent mind. Shakespeare also uses it to show us the depth and strength of her love and of her resilient personality. She probably wishes she could throw herself on Romeo's body there and then.

Clearly, there is much irony in the passages relative to the question on  William Shakespeare's tragedy, Romeo and Juliet.   First of all, there is verbal irony as Juliet pretends to agree with her mother, saying,

Indeed I never shall be satisfied

With Romeo till I behold--him--dead (III,v.96-97)

Juliet does not mean what her mother construes; rather, she means that she will never tire of Romeo until he is dead and gone from her, hopefully, when they are old.  However, the second irony, that of dramatic irony, present in these lines is that Juliet, indeed, will see Romeo dead. 

This passage is also significant because it furthers the motif of fate.  The "star-crossed lovers" will again meet, but meet in tragedy.

This comes from Act III, Scene 5.  Lady Capulet is angry at Romeo for killing Tybalt.  When she talks about poisoning him, Juliet says these lines:

Madam, if you could find out but a man
To bear a poison, I would temper it;
That Romeo should, upon receipt thereof,
Soon sleep in quiet. O, how my heart abhors
To hear him named, and cannot come to him.
To wreak the love I bore my cousin
Upon his body that slaughter'd him!

What is going on here is that she is pretending to agree with her mother.  She is sounding like she really hates Romeo, but you can read what she says in another way.

She says that she would want to do something to make sure Romeo sleeps in quiet.  Her mother thinks she means death, but she means it literally.  The same goes for the last lines -- she implies that she wants to hurt Romeo's body, but she means she wants to show his body a lot of love...