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: friction is used for stopping a vehicle by brakes.

Output: braking cars can fishtail.


Input: Consider Input: Fact: electricity is used as an energy source by electrical devices.

Output: device phone.


Input: Consider Input: Fact: glass cause refraction of light.


Output: glass mirror.