Answer:
Grunkle Stan Pines baked a cake but forgot to add sugar; therefore, he took one bite and spit it out.
OR
Grunkle Stan Pines baked a cake but forgot to add sugar. Therefore, he took one bite and spit it out.
Explanation:
What is "Grinkle Stan Pines" ??
"Therefore" is not the appropriate word here, but your instructions say to correct only capitalization and punctuation errors.
Explanation:
Nick said it because of his previous experiences which were not so easy to handle and that have transformed his thoughts so much that he considered that his future would be same as his past. He even didnt remember his birthday, indicating that his mind is well occupied by the menacing experiences and thoughts. Since he has turned thirty so now people think its time to settle but for Nick its still a road of struggle ahead of him