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.

Ex Input:
Fact: living things all require energy for survival.

Ex Output:
energy food.


Ex Input:
Fact: extreme heat and pressure change rock into metamorphic rock.

Ex Output:
earth's core creates extreme heat.


Ex Input:
Fact: Earth 's tilt on its rotating axis causes seasons to change.

Ex Output:

fall winter seasons.