听下面一段较长对话,回答以下小题。
13. How many bones are there in the human body?
14. Which is the function of bones?
A.Keeping people healthy. |
B.Moving along the ground. |
C.Protecting the insides of the body. |
15. Which food is good for bones according to what the man said?
16. Why should people do regular exercise?
A.Make their bones strong. |
B.Weaken their muscles. |
C.Provide a structure. |