[Q]: How does the sentence end?

Christine but not Rachel had nightmares because 
OPTIONS:
- Christine remembered the creature they saw at the zoo.
- Rachel remembered the creature they saw at the zoo.

[A]: Christine remembered the creature they saw at the zoo.
QUES: Continue writing.

Bob poured the entire bowl of chips into his mouth for lunch until the 

OPTIONS:
- bowl was empty.
- mouth was empty.
+++++++++
ANS: bowl was empty.
Problem: How does the sentence end?

The winning horse was given a apple and a steak, but the horse liked to eat the 
OPTIONS:
- apple .
- steak .
Answer: apple .
sentence: Lindsey really got Elena's blood pumping when  OPTIONS:
- Lindsey pushed them to keep exercising even after they were tired.
- Elena pushed them to keep exercising even after they were tired.
complete: Lindsey pushed them to keep exercising even after they were tired.
Mary got stranded along the side of the road, and Christine helped them, so 
OPTIONS:
- Mary was kind.
- Christine was kind.
Christine was kind.
Problem: Continue the following story.

He tried to cut the slate with a knife but it didn't work because the 
OPTIONS:
- slate was so dull.
- knife was so dull.
Here's how I want to continue it:
knife was so dull.