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: Cytoplasm refers to all of the cellular material inside the plasma membrane.

Ex Output:
a membrane is.


Ex Input:
Fact: Caffeine is an example of a psychoactive drug.

Ex Output:
caffeine psychoactive.


Ex Input:
Fact: a valley is formed by a river flowing.

Ex Output:

colorado river flow.