Answer:
Romeo thought Juliet was dead when he poisoned himself, but the audience knew she was alive.
Step-by-step explanation:
In Act V Scene III, Romeo enters the tomb where Juliet lay dead. After killing Paris in a fight, Romeo admires the beauty of Juliet. He thinks that Juliet is dead because of which he also decided to end his life. He drank the poison and died. In this scene, the dramatic irony in this situation. The audience was known about the fact that Juliet was alive but Romeo was unaware of the fact. Such situations in which the audience know more than the characters, dramatic irony arises.