Problem: How does the sentence end?

The man tried to hide the diamond in the safe but the 
Answer: safe was too small.

Problem: How does the sentence end?

Betty projects much more happiness than Amy, 
Answer: Betty because/although she smiles a lot more often.

Problem: How does the sentence end?

She had a cold and decided to ditch the vitamins and use medicines, because the 
Answer: medicines were more effective.

Problem: How does the sentence end?

Mike wanted an aquarium instead of a fish bowl. The 
Answer:
aquarium could hold a lot more fish.