Problem: How does the sentence end?

Randy wanted to give the living room a coat of paint but Kyle did not because
Answer: Kyle was disinterested in DIY.

Problem: How does the sentence end?

The company built the structure using steel but not iron because the
Answer: steel was integral.

Problem: How does the sentence end?

Amy wanted to go back to work after retiring but Carrie did not because
Answer: Carrie was occupied.

Problem: How does the sentence end?

Rachel gave Samantha a written warning on their performance because
Answer:
Samantha was negligent about fixing workplace issues.