呼吸运动就是吸气和呼气这两个动作 进行。呼吸运动是 和 运动的结果。
连续交替 肋骨 胸骨
.Saving resources is a basic policy of our country . And it proves _____ to its sustainable development .
A．to be great significance
B．to be of great significant
C．of great significance
D．great significant
治疗下肢急性丹毒，应首选
A．青霉素B．红霉素C．庆大霉素D．四环素
