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: matter vibrating can cause sound.

Output: cause sound.


Input: Consider Input: Fact: water vapor cooling causes that water vapor to condense.

Output: fogged mirror condensation.


Input: Consider Input: Fact: Brain cells die quickly if their oxygen supply is cut off.


Output: brain cell die.