题目

If parents have children help with housework, the children will feel needed. , they will learn to take care of themselves. A. On the contrary                      B. In a word C. That is to say                       D. What’s more 答案：D坐在温馨的物理考场，仔细想想：你平时走路的步幅约为50     ，上体育课时你跑100m所需时间约为16     （填上合适的物理量单位）．