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: Viruses contain DNA but not much else. 
Fact 2: Viruses are germs that cause people to get sick.
Example Output: germs that cause people to get sick contain DNA but not much else.

Example Input: Fact 1: lakes are formed by precipitation and runoff. 
Fact 2: The Caspian Sea is, strictly speaking, not really a sea but instead the world's largest lake.
Example Output: The Caspian Sea was formed by precipitation and runoff.

Example Input: Fact 1: cycles of freezing and thawing water cause ice wedging. 
Fact 2: The fact is that ice seldom freezes or thaws at a uniform rate.
Example Output:
ice wedging happens at varying rates.