Problem: How does the sentence end?

Michael kept their motor well maintained but Dennis ignored their engine maintenance. 
Answer: Dennis spent a lot of money on car repairs.

Problem: How does the sentence end?

Robert put a wad of gum in Michael's hair, which led to 
Answer: Robert  spending a day in detention.

Problem: How does the sentence end?

When it comes to being stealthy, Amy is much better than Laura due to 
Answer: Amy being a commando.

Problem: How does the sentence end?

Going to jazz festivals was entertaining to Christine but not Erin because 
Answer:
Christine enjoyed large crowds.