4. In the beginning, man’s life was dictated by two factors that were beyond his control: night and day, darkness and light. Night brought about an environment inwhich action had to cease, so man repaired to his cave, wrapped himself with his furs and went to sleep. Or he climbed a tree and made himself as comfortable as hecould while awaiting the coming of dawn. Day brought an environment in which action was possible, so he set forth once more to replenish his store, forage or hunt forhis food. Night brought passivity, quiescence, and a general slowing down of metabolic and glandular activity. Day brought with it the possibility of action, anincrease in metabolic rate and a greater glandular secretion, thus providing him with both energy and incentive. Night and day were the keys to man’s activities.Controlling Idea:___________________________________________________________________Clinching sentence: ___________________________________________________________________Type of clinching sentence: ___________________________________________________________________