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: killing microorganisms in food can be used to extend the shelf life of that food. 
Fact 2: Irradiation kills microorganisms that spoil food.

Output: Irradiating food can extend shelf life by removing microorganisms.


Input: Consider Input: Fact 1: Flagella help prokaryotes move. 
Fact 2: Some species swim by means of flagella Bacterial flagella are analogous to flagella of eukaryotes.

Output: prokaryotes and Bacteria move by swimming.


Input: Consider Input: Fact 1: Bioterrorism is another potential threat in the environment. 
Fact 2: Humans depend on their natural and constructed environments.


Output: bioterrorism is a threat to humans.