She will tell us why she feels so strong that each of us has   a role________in making the earth a better place to live in.

A．to have played　

B．to play

C．to be played 　

D．to be playing

符合全脊髓麻醉的叙述的是

A．死亡率低
B．是硬膜外隙阻滞所用麻醉药物进入蛛网膜下隙所致
C．主要表现为呼吸兴奋、血压升高
D．是硬膜外隙阻滞特有的并发症
E．发生缓慢