某河多年平均流量为13m3/s，河流断面形状为矩形，河宽12m，在取样断面上应设( )取样垂线。
A．一条
B．二条
C．三条
D．四条
参考答案：A
女性，22岁，2年来反复痰中带血，间有大口咯血。体格检查无异常体征，X线胸片示左下肺纹理增粗、紊乱。最可能的诊断是
A．风湿性心脏病二尖瓣狭窄
B．慢性支气管炎
C．支气管扩张症
D．支气管肺癌
E．肺结核
— Where are the Greens, may I ask?
— Well, they ______ to England. They have been there for nearly a week now. [ ]
A. have been
B. are going to
C. have gone
D. will go
