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: a speedometer is used for giving a driver feedback on the speed of their vehicle. 
Fact 2: Speed is the magnitude of velocity.
Example Output: A speedometer is used for giving feedback on the velocity of a vehicle.

Example Input: Fact 1: Insects may live in large colonies and have complex social behaviors. 
Fact 2: Ants and butterflies are insects.
Example Output: ants may live in large colonies.

Example Input: Fact 1: Smog contains particulates. 
Fact 2: Particulate matter varies in size.
Example Output:
Smog contains matter that varies in size.