Problem: How does the sentence end?

Mark wanted to buy himself a new golf ball but ended up buying a tennis ball for his son, because the 
Answer: tennis ball is more important for his family.

Problem: How does the sentence end?

The surgeon was trying to perform a episiotomy by using a needle incision, but was unable to begin as the 
Answer: incision was too small.

Problem: How does the sentence end?

Natalie was more energetic than Betty because 
Answer: Betty had been running on the treadmill all day.

Problem: How does the sentence end?

Katrina's home isn't nearly as clean as Elena's because 
Answer:
Katrina has always been a messy person.