Teacher: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.
Teacher: Now, understand the problem? Solve this instance: Fact 1: Earth 's tilt on its rotating axis causes seasons to change. 
Fact 2: Seasons are caused by the motion of the Earth around the Sun and the tilt of the Earth's axis.
Student:
seasons change because of tilt.