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: creating paper requires cutting down trees.
Example Output: cutting down trees causes harm to environment.

Example Input: Fact: when a hemisphere is tilted towards the sun , that hemisphere receives more direct sunlight.
Example Output: direct during sunlight summer.

Example Input: Fact: lungs are used for breathing air by land animals.
Example Output:
breathing.