提高肝外胆管下段显示的方法有①饮水②脂餐③胸膝位④侧转探头
A．①
B．①②
C．①②③
D．①②③④
E．①③④
参考答案：D
— How could you be so impolite when there were so many guests in the party?
— _____________. [ ]
A. Nothing serious
B. Never again
C. Never mind
D. Not enough
春天百花盛开，空气中弥漫着花香，这是一种 ______现象．小华在实验中发现，两滴互相靠近的水银，能自动的汇聚成一滴，这表明水银分子之间存在着 ______．
