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: Courtship is behavior that is intended to attract a mate. 
Fact 2: Almost all animals display colors to attract a mate or to scare off a predator.
Example Output: Courtship can be manifested by displays of color.

Example Input: Fact 1: a car engine usually converts gasoline into motion and heat through combustion. 
Fact 2: Combustion is never complete in gasoline and diesel engines.
Example Output: Cars never completely convert gasoline into motion.

Example Input: Fact 1: Urine is the liquid waste product of the body that is excreted by the urinary system. 
Fact 2: Liquid waste is put into the bladder.
Example Output:
Urine is the waste product in the bladder that is excreted by the urinary system.