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.

Example Input: Fact: Most bryophytes are small.
Example Output: bryophytes plants.

Example Input: Fact: an electron microscope is used for seeing very small objects by making them appear bigger.
Example Output: atoms are small.

Example Input: Fact: Biomass is the total mass of organisms at a trophic level.
Example Output:
biomass organism.