In this task, you are given a sentence with a missing word that can be an object, a person, and/or an action. Fill in the blank with a plausible word. Although each sentence has many correct answers, you only have to write one answer.
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Question: PersonX fills PersonX's ___ with air

Answer: mattress


Question: PersonX exceeds ___ in weight

Answer: hippos


Question: PersonX divides ___ into classes

Answer:
notebooks