A:was it that
B:that it wa
C:that was it
D:it was that
Would you when you are in town?
如图是气体交换与血液循环的关系示意图(图中7表示肺泡,8表示组织细胞),请据图分析回答下列问题:
实现人生的意义,追求生命的价值,要____、从____做起,从____做起。