请结合自己的身体，说明一下人体的结构层次为：____→____→____→____→人体．

A: Hi, Bob! How was your last weekend?

B:____ I really had a good time.

A:____ 

B: I played basketball.

A:____

B: Twice a week. I like it very much. How did you spend your last weekend?

A:____

B: Sounds interesting. Do you often go to the mountains?

A: Yes. Once a week.____

B: I'd love to. But I'm afraid I can't go with you this weekend. Maybe next week is OK.

如图漫画告诉我们，人生价值的实现（    ）