分解槽结疤是怎么形成的？
长江中游新石器时代的重要遗址有（） ["大溪文化","马家窑文化","屈家岭文化","仰韶文化"]
The period of a lighted aid to navigation refers to the（）. ["date of construction or establishment","length of time between flashes of the light","time required for the longest flash of each cycle","time required for the light to complete each cycle"]
下列关于南唐画家董源说法正确的是（）。 ["画法基本上有两种，一是水墨山水，另一种是设色山水","代表作有（寒林重汀图）轴、《溪岸图》轴、《洞天山堂图》轴等","就作品的总体风格而言，董源以韵胜，而巨然则以势胜","《潇湘图》卷在其传世作品中具有代表性"]
ULGrant是在哪个信道进行传送（）。 ["PUCCH","PDSCH","PUSCH","PDCCH"]
风管堵塞的原因是什么，如何处理？
