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.

Q: Fact: condensation causes clouds to form.

A: clouds cause rain.
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Q: Fact: Echinoderms lack respiratory and excretory systems.

A: Echinoderms starfish.
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Q: Fact: fanning a fire increases the oxygen near the fire.

A:
fanning fire flames.
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