Combine the given two facts to write a concluding fact. Note that there should be some parts of the first and second facts that are not mentioned in this conclusion fact. Your combined fact should be the result of a chain between the two facts. Chains form when two facts connect together to produce a concluding fact. An example of a chain is: "pesticides cause pollution" (fact1) + "pollution can harm animals" (fact2) → "pesticides can harm animals" (conclusion fact). Parts of the concluding fact overlap with the first and the second fact. To construct such a  concluding fact, a useful way is to borrow the subject from one fact and the ending conclusions from another fact.

Example Input: Fact 1: Light enters the eye through an opening called the pupil. 
Fact 2: Light is essential to vision.
Example Output: vision requires the pupil.

Example Input: Fact 1: Bacteria may spread directly from one person to another. 
Fact 2: People can be infected or killed by the bacteria.
Example Output: People can spread death from one person to another.

Example Input: Fact 1: camouflage is used for protection by prey against predators. 
Fact 2: Camouflage blends the best in shadows.
Example Output:
blending is used for protection.