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.

Input: Consider Input: Fact: a light bulb requires electrical energy to produce light.

Output: coal can be used to create electricity.


Input: Consider Input: Fact: Roundworms make up the phylum Nematoda.

Output: Nematoda.


Input: Consider Input: Fact: an animal requires nutrients to grow and heal.


Output: animal nutrients.