Problem: How does the sentence end?

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

Problem: How does the sentence end?

Randy would have flunked out of school if not for Brett 's tutoring since 
Answer: Brett was a superior student.

Problem: How does the sentence end?

The ceiling in my house was better than the roof on Johns because the 
Answer: roof had a leak.

Problem: How does the sentence end?

My friend's handgun is in worse condition than my pistol because the 
Answer:
pistol was left in a safe.