哪项因素对硬膜外麻醉平面调节最重要
A．注药方式B．注药速度C．病人体位D．药物浓度E．药物种类
参考答案：A
—Tom is so worried about the test that he said he was going to study all night.
—Tell him he should quit ______ and get some help.
A．to have worried
B．to worry
C．worrying
D．from worrying
互联网是社会大众共有的虚拟世界，但不应是绝对的自由平台。
