Question

Struggling, unpublished writers are sure that publishers, who seek out and publish new authors, are nonexistent.

Answer 1

Answer:

Omit the last two commas.

Explanation:

Struggling; unpublished writers are sure that publishers who seek out and publish new authors are nonexistent.

We omit the last two commas because all the sentence is the same idea and when we use commas it is because we want to express different ideas or make pauses and in this context it is not necessary. Also, I will say that in the first part after the word struggling we use a semicolon in order to make emphasis about the next elements of the idea.

Answer 2

Here is the full question:
Struggling, unpublished writers are sure that publishers, who seek out and publish new authors, are nonexistent.
Find and correct the error in this sentence

The correct sentence should be without the second comma:
Struggling, unpublished writers are sure that publishers who seek out and publish new authors are nonexistent.
 publishers who seek out and publish new authors are nonexistent is a part of one clause that does not possess two different meaning, so it should not be separated by a comma.
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