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: Secondary growth forms secondary vascular tissues and bark. 
Fact 2: Trees have the ability to undergo secondary growth and produce a woody body.
[A]: trees form secondary vascular tissues and bark.


[Q]: Fact 1: Electron transport is the final stage of aerobic respiration. 
Fact 2: Electron transport is like a waterfall.
[A]: Transport like a waterfall is the final stage of aerobic respiration.


[Q]: Fact 1: gases from burning coal and oil dissolving in water in the atmosphere causes acid rain. 
Fact 2: Acid rain is precipitation which pH is 5.7 or lower.
[A]:
gases from burning coal causes precipitation which pH is 5.7 or lower.