The essential appositive in the sentence "astronomer maia mitchell discovered a comet in 1847 and went on to become the first professional female astronomer in the united states," is Maia Mitchel. The last option is correct.
An appositive consists on a noun or noun phrase that renames another noun right beside it. The appositive can be a short or long combination of words.
In this particular case, the words Maia Mitchell which is a proper noun is renaming the noun astronomer, which is right before it and constitutes the subject of the sentence.
Jimmy studied hard for his test- He will get a good grade.
Justin did great on his homework- Justin will receive a good grade for his homework.
Practiced reading every night- She is a good reader now.
Where is the text? If you attach the text, then I can help you write the conclusion.
Changing the sentence from a very long sentence into a short and choppy helps the suspense by not giving the reader a lot of information and making them really think and wonder.
For example:
"The stranger watched, a look in his eyes and this feeling spread throughout my body."
or
"There was a man watching, his blue eyes had this look in them that made me shiver with fear. His pale face held no emotion and made him seem as if he was just a corpse standing on his own."
The second one might sound better, yes, but the second one really makes you think and really builds the suspense.
"Who is this stranger? What does he look like? What feeling spread throughout their body?"
So instead of knowing a lot about this stranger, you know little to nothing and it really makes you want to know more, and definitely build the suspense.
