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: dehydrating food is used for preserving food. 
Fact 2: Dehydration is the removal of water.
Example Output: Removing water preserves food.

Example Input: Fact 1: eyes are used for seeing by animals by sensing light. 
Fact 2: Light waves are electromagnetic waves.
Example Output: eyes are used for seeing by animals by sensing electromagnetic waves.

Example Input: Fact 1: Hookworm larvae enter the host through the skin. 
Fact 2: When larvae are swallowed by the cat, hookworm infection is established.
Example Output:
hookworm infection is established when hookworm enter through the skin.