Problem: How does the sentence end?

The ventilation in the city was more polluted than the air in the forest, because the 
Answer: ventilation was dirty.

Problem: How does the sentence end?

Cynthia showed Sarah how to make the best witch costume for Halloween since 
Answer: Cynthia knew she was hoping to win a prize with her costume.

Problem: How does the sentence end?

Emily told Maria that she was going to be more thoughtful this new year.  
Answer: Maria was skeptical.

Problem: How does the sentence end?

Quentin left the college and went to a new school in a neighboring city because the 
Answer:
college had negative reviews.