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: All animals are heterotrophs.

Ex Output:
All animals are heterotrophs.


Ex Input:
Fact: Immunodeficiency occurs when the immune system is not working properly.

Ex Output:
immune system keeps people healthy.


Ex Input:
Fact: Platypus females lay their eggs in a burrow.

Ex Output:

burrow area.