In this scene Romeo explains how he is a “boat” and how God is the captain, leading him to his fate, a bit like following a trail of bread crumbs. Already we can identify that a metaphor has been used as he isn’t really a ship and is just describing the course of his life. This specific scene is vitally important to the whole play as it ties the play together and links back to the main idea of FATE.
Again, in Act 4 scene 2 Juliet has just been told the plan of her pretending to be dead and how Romeo and Friar Lawrence will soon be there to pick her up. She then goes tell her father that she is willing to marry Paris (which she isn’t really). Right there in bold is where the dramatic irony comes in, as the audience knows she doesn’t really want to marry him.