Generate a sentence that answers this question: "A source of heat could be".

Answer: a radiator is a source of heat

Generate a sentence that answers this question: "What is animal competition?".

Answer: if two animals eat the same prey then those animals compete for that pey

Generate a sentence that answers this question: "The back and forth on daily routine in the sky happens how often?".

Answer:
cycles of day and night occur once per day