You'll be alert, engrosed in the (14)material.And concentrated 100 percent.

a) no change
b) material, and
c) material; and
d) material and

After reading it over and over,
I think b) a comma after material
would be the correct answer.

I think this is a compound sentence, since material is the subject for verb 'engrossed' is that
right?

B is correct; however, it is not a compound sentence. It is a simple sentence with compound predicate adjectives = alert, engrossed, concentrated.

thanks : )

Yes, you are correct! In this sentence, the phrase "alert, engrossed in the (14) material" is describing how the subject of the sentence is behaving. The subject of the sentence is "you," and the phrase is modifying how "you" are behaving.

Now, let's analyze the options to see which one is correct.

a) "no change" - This option suggests that the original sentence is correct and doesn't need any modifications.

b) "material, and" - This option adds a comma after the word "material." A comma is often used before the coordinating conjunction "and" when it connects two independent clauses in a compound sentence.

c) "material; and" - This option replaces the comma with a semicolon before the conjunction "and." Semicolons are typically used to join independent clauses in a compound sentence when there is a stronger connection between the clauses.

d) "material and" - This option removes the comma altogether.

Based on the context of the sentence, option b) "material, and" is the correct answer. The use of a comma before "and" helps to indicate that "alert" and "engrossed in the (14) material" are two separate ideas modifying the subject "you."