Problem: How does the sentence end?

Elena commands more attention than Erin since 
Answer: Erin is often quite shy with a small social circle.

Problem: How does the sentence end?

A jet ski was purchased from Erin to give to Angela because 
Answer: Angela was very manipulative.

Problem: How does the sentence end?

Steven dropped out of marathon training while Derrick trained harder. 
Answer: Steven had already suffered a bad ACL injury.

Problem: How does the sentence end?

Elena thought strawberries were delicious but Natalie hated their taste. 
Answer:
Natalie had blueberry shortcake for their dessert.