请问是keys to exercise 1还是key to exercise 1

请问是keys to exercise 1还是key to exercise 1 英语翻译THE KEYS TO ZHE EXERCISE（翻译成汉语）第一个翻译是用TO还是 OF? they like to exercise 还是they like to do exercise exercise to do sth还是 exercise doing sth? Exercise 1: manage to diet and exercise还是manage to diet and to exercise, 是take exercise 还是take the exercise? 八年级英语单项选择※The key ____this exercise is in our textbook.A、to 貌似有exercise to do why i need to exercise? ____healthy,you should take more exercise.请问是to keep healthy ___you should take more exercise to keep healthy,是maybe还是 ma