In this task, you need to write a topic word from the given fact. The topic word must have at least one word overlap with the given fact. The topic word often involves adding a new word from a related concept. In your topic word, use at least one word from the given fact. Topic words with two or more words work best.
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Question: Fact: contact between rocks over long periods of time causes rocks to smooth.

Answer: Rocks are formed.


Question: Fact: Amphibians have a relatively complex circulatory system with a three-chambered heart.

Answer: amphibian frog.


Question: Fact: Plants use cellulose for their cell walls.

Answer:
cell walls.