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: using a gasoline engine requires burning gasoline. 
Fact 2: Oil and gasoline are fossil fuels.

Output: Many engines burn fossil fuels.


Input: Consider Input: Fact 1: thick fur can be used for keeping warm. 
Fact 2: With a thick fur coat and 4 inches of fat a bear stays warm.

Output: Bears have thick fur to protect from the cold.


Input: Consider Input: Fact 1: Fertilization occurs when sperm swim to an egg inside an archegonium. 
Fact 2: Pregnancy begins with a fertilized egg.


Output: Pregnancy begins after sperm swim to an egg inside an archegonium.