When we were young, every evening my brother and I ______ stay at home waiting for our mother to come back from work.

A．would

B．might

C．should

D．could

铁路运输成本费用预测的内容主要有（）。

A.预测一个新工人对成本的影响

B.预测成本费用计划各项指标的总体水平

C.预测采用新技术、新设备、新材料对成本费用的影响

D.预测价格、运量等因素变化对成本费用的影响

E.预测更改生产结构对成本费用的影响