What is the simple subject of this sentence The book Exodus hard to read?

The simple subject of the sentence "The book Exodus is hard to read" is Exodus.

Here's why:

* Simple subject: The main noun or pronoun that performs the action of the verb.

* "The book Exodus" is a noun phrase that functions as the subject.

* "Exodus" is the noun within the phrase that is the actual subject of the verb "is".