In this task, you're given a four sentences of story written in natural language. Your job is to complete end part of the story by predicting appropriate last sentence which is coherent with the given sentences.

Q: Sentence1: Frank filled up dozens of water balloons to throw at this sister. Sentence2: Little did he know she was ready for him. Sentence3: When he started the attack, she pulled out a huge water gun. Sentence4: It was much more effective than his balloons.

A: Frank bought a water gun the next day.
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Q: Sentence1: A police officer came down with the flu today. Sentence2: He was unable to go into work as he could barely get out of bed. Sentence3: His wife spent time taking care of him and making sure he was okay. Sentence4: He made sure to drink enough and eat enough.

A: The police officer eventually got better.
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Q: Sentence1: Donna realized it was finally time to potty train her son. Sentence2: She went and bought him a training toilet and pull ups. Sentence3: She worked with him by showing him how to use the potty. Sentence4: He really struggled and didn't seem to understand.

A:
One day Donna saw her son use his potty on his own.
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