The mood which is established bu the setting, especially in the use of words such as deep, dusk, and black is <em>dark, gloomy, depressing, sad, scary, mysterious, </em>etc.
Hello There
Answer: I don't believe they are acting irresponsibly because they are trying to help Romeo and Juliet be happy. They know that their parents hate each other and they think that that shouldn't stop them from being happy together
I hope this helps
-Chris
