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.
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Question: 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.

Answer: Cars never completely convert gasoline into motion.


Question: Fact 1: Minerals are chemical elements that are essential for body processes. 
Fact 2: Healing is a natural process for the human body.

Answer: Minerals are chemical elements that can help with healing.


Question: Fact 1: Reproduction is the process by which living things give rise to offspring. 
Fact 2: Most people want to have children who are the biological offspring of both parents.

Answer:
Reproduction is the process by which living things produce children.