当槽底土体遇有原暗浜或流砂现象，沟槽降水措施不良或井点失效，处理时间过长，直接造成已浇筑的水泥混凝土基础拱起甚至开裂。
参考答案：对
若a，b互为相反数，那么2006（a+b）=（ ）。
--People should use public transport instead of their own private cars.
--- _______.The roads are too crowded as it is.
A．Eventually
B．Exactly.
C．Particularly
D．Actually.
