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: Cells cannot survive without oxygen. 
Fact 2: Survival is to live, to live means hope.

Output: Cells cannot live without oxygen.


Input: Consider Input: Fact 1: a warm front causes cloudy and rainy weather. 
Fact 2: If warm air is advancing on cold air, the front is designated a warm front.

Output: Warm air advancing on cold air can lead to cloudy and rainy weather.


Input: Consider Input: Fact 1: Blood pH may become unbalanced if the rate of breathing is too fast or too slow. 
Fact 2: Breathing is regulated to keep as normal as possible arterial blood pH and PO2.


Output: Breathing is regulated to keep blood acidity balanced.