天然气从气田的井口开始,经矿场集气、净化、干线输气,直到通过配气管网送到用户,形成了一个统一的、()的天然气输送系统。
A.环状
B.放射式
C.密闭式
D.网络式
参考答案:C
水泥的出厂检验项目为()。
A、化学指标
B、凝结时间
C、安定性
D、强度
For all the remaining items the stated dates of delivery are approximate, but () would these dates be exceeded by more than ten days.
A. in no case
B. in any case
C. under any circumstances
D. by all means