咽喉部手术麻醉最关键的是（）
A.保持呼吸道通畅
B.维持血压平稳
C.镇痛
D.镇静
E.肌松完善
参考答案：A
—Maria is wanted on the telephone. Where is she?
—She _________ the library. You can find her there。
A．has been to
B．has gone to
C．has left
D．has been in
日常观察
