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: a valley is formed by a river flowing. 
Fact 2: Rivers erode the rocks they flow over.
[A]: Water erodes rocks as they flow over, creating a valley.


[Q]: Fact 1: Biodiversity generally increases from the poles to the equator. 
Fact 2: Soil Biodiversity Soil biodiversity reflects the mix of living organisms in the soil.
[A]: the mix of living organisms generally increases from the poles to the equator.


[Q]: Fact 1: Plants use cellulose for their cell walls. 
Fact 2: Leaf blades contain cellulose and hemi-cellulose that are readily broken down by microbes.
[A]:
plants cell walls are readily broken down by microbes.