question: What sentence would provide a factual answer to this question: "What can build something over millions of years?"

answer: a canyon forming occurs over a period of millions of years

question: What sentence would provide a factual answer to this question: "chemical reactions cause"

answer: chemical reactions cause chemical change

question: What sentence would provide a factual answer to this question: "Aside from plants, lizards also eat bugs for"

answer:
lizards eat insects