源于橘的干燥幼果或未成熟果实的干燥果皮的药物是（）
A.橘络
B.橘红
C.橘核
D.青皮
E.化橘红
参考答案：D
(2011·全国卷Ⅰ)They ________have arrived at lunchtime but their flight was delayed.
A．will
B．can
C．must
D．should
矿井通风系统如何设置？
