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.

Input: Consider Input: Fact 1: carpooling decreases the amount of cars used to travel to a place. 
Fact 2: And fewer cars means less pollution.

Output: carpooling leads to less pollution.


Input: Consider Input: Fact 1: a valley is formed by a river flowing. 
Fact 2: Examples are Napa Valley and Sonoma Valley.

Output: Napa and Sonoma were formed by a river flowing.


Input: Consider Input: Fact 1: Mutations may change the structure of a chromosome or just change a single nucleotide. 
Fact 2: Mutagenic chemicals cause mutations.


Output: Mutagenic chemicals may change the structure of a nucleotide.