引起便血伴发热、少尿的常见疾病是（）。
A.肠结核
B.直肠癌
C.白血病
D.消化性溃疡
E.流行性出血热
参考答案：E
My calculations were based on the ________ that house prices would remain steady.
A．theory
B．assumption
C．procedure
D．regulation
开凿或延深斜井和下山时，在斜井或下山的上口，必须设有什么样的装置？
