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.

Q: Fact 1: if a planet becomes too hot then that planet cannot sustain life. 
Fact 2: If a planet is too close to a star, then it will be too hot for liquid water to exist.

A: If a planet is too close to a star, that planet cannot sustain life.
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Q: Fact 1: condensing means changing from a gas into a liquid by reducing heat energy. 
Fact 2: Heat is the energy of moving molecules.

A: condensing means changing from a gas into a liquid by reducing moving molecules.
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Q: Fact 1: the type of material through which sound passes changes the speed at which sound travels. 
Fact 2: Refraction is the effect on a wave when there are changes in a medium.

A:
Differences in the speed of sound cause sound waves to be refracted when passing between different media.
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