Hello. You didn't show which words are underlined, so I'll give you the grammatical name and function of all of them.
What: Pronoun. It has the function of referring to or replacing a noun, representing something, which does not have a specific name, but which needs to be represented in the sentence. The pronoun is a variable word.
To do: Verb. It has the function of representing an action, an activity that will be performed by something or someone.
Is: Verb. It has the ability to represent a state or occurrence.
Problem: Noun. It has the function of naming something or someone.
Answer:
I don't know what to do for this subject
The mood created at the beginning of "The Raven" is one of mystery and sadness with undertones of horror. Poe accomplishes this through the Gothic setting, characterization
The meaning of the word incredulous, based on its parts is: "full of disbelief".
The prefix in- is one of the many prefixes that mean "no". So it denies the meaning of the word following it. One example would be the word inefficient. By adding the prefix in- to the adjective efficient, we deny the adjective. If we call a person inefficient, we are saying the person is "not efficient", not able to finish tasks in a proper time and manner.
As for the other part of the word we're analyzing here, "credulous" comes from the Latin word "credere", which means "believe". A credulous person is a person who believes in things easily, without questioning or reasoning.
By putting in- and credulous together, we form "incredulous", or "not credulous". So an incredulous person is a person who does not believe easily - who is full of disbelief.
I'm pretty sure it wasn't shown in the play.