Problem: How does the sentence end?

Donald asked Justin to help with writing the paper since 
Answer: Justin was skilled at writing.

Problem: How does the sentence end?

Making play dough only required two ingredients which Kyle had on hand, but not Eric, so 
Answer: Kyle finished the project quickly.

Problem: How does the sentence end?

Monica frequently avoided hanging out with Tanya, because 
Answer: Tanya was an egocentric who just wanted to be invasive.

Problem: How does the sentence end?

Robert wore their hair in braids but Benjamin did not as 
Answer:
Benjamin had short hair.