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: Yeast reproduce asexually by budding.
Example Output: Yeast.

Example Input: Fact: the surface of a beach is formed by mechanical weathering.
Example Output: beach erosion.

Example Input: Fact: Weather refers to the conditions of the atmosphere from day to day.
Example Output:
An atmosphere is a layer of gases surrounding a planet.