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.

Fact: if an object is made of a material then that object has the properties of that material.
Material is a substance.

Fact: the force of water against the seed coat causes a root to emerge from a seed.
a root to emerge from a seed.

Fact: chlorophyll is used for absorbing light energy by plants.

chlorophyll all green plants.