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: skin is used for breathing air by frogs. 
Fact 2: Air contains oxygen.
Example Output: skin is used for breathing oxygen by frogs.

Example Input: Fact 1: sunlight and rain can cause a rainbow. 
Fact 2: Rain comes from clouds.
Example Output: sunlight and clouds can cause a rainbow.

Example Input: Fact 1: Roots grow in length and width from primary and secondary meristem. 
Fact 2: Growth in girth is caused by other meristems, called secondary meristems.
Example Output:
Roots grow in length and girth caused by meristems.