Problem: How does the sentence end?

The graphic novel that Robert wrote sold fewer copies than Michael, so 
Answer: Michael is the more advanced writer.

Problem: How does the sentence end?

the doors was too small to let the car through for  a car wash, the 
Answer: car was too big.

Problem: How does the sentence end?

Dennis's business flourishes while Michael's is failing; I guess 
Answer: Michael must be a lazy worker.

Problem: How does the sentence end?

The doctor recommended diet and exercise to lose the weight but she struggled because the 
Answer:
exercise was so strenuous.