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.

Fact 1: Lions live in social groups called prides. 
Fact 2: Leo's symbol is the lion.
Leo's symbols live in social groups called prides.

Fact 1: lakes are formed by precipitation and runoff. 
Fact 2: The Caspian Sea is, strictly speaking, not really a sea but instead the world's largest lake.
The Caspian Sea was formed by precipitation and runoff.

Fact 1: Weather refers to the conditions of the atmosphere from day to day. 
Fact 2: Rain is a different type of weather.

Rain is a condition of the atmosphere.