Problem: How does the sentence end?

Eric made a birthday cake for Michael because 
Answer: Eric wanted to celebrate the special occasion.

Problem: How does the sentence end?

Craig agreed to water Randy's plants while they were away since 
Answer: Craig did not go on vacation.

Problem: How does the sentence end?

The woman took the sheets off the bed but left the blankets on, because the 
Answer: blankets were clean.

Problem: How does the sentence end?

The red wine stain stood out on the white carpet because the 
Answer:
stain was very dark.