Problem: How does the sentence end?

The tornado demolished the house but left the barn intact, as the 
Answer: barn was a rugged structure.

Problem: How does the sentence end?

Sarah had to ask Laura for help with setting MAC keyboard shortcuts because 
Answer: Laura always used MACs.

Problem: How does the sentence end?

Erin informed Jessica the importance of dandelions because 
Answer: Jessica  didn't know the dangers to the bees.

Problem: How does the sentence end?

Donald asked Randy to make some delicious chocolate brownies because 
Answer:
Donald was not a good baker.