运输服务的购买者向运输市场所提出的一种有货币支付能力的要求，称之为( )
A．运输欲望B．运输需求C．运输劳务D．运输供给
参考答案：B
句型转换(每空一词)。
1. Miss Zhang gives us a talk. (用next week改写)
Miss Zhang _____ _____ _____ _____ us a talk next week.
2. We had a good time in the party yesterday. (改为同义句)
We _____ _____ in the party yesterday.
3. They are going to stay in Beijing for a long time. (对画线部分提问)
_____ _____ are they going to _____ _____ Beijing?
4. They are going to San Francisco. (对画线部分提问)
_____ are they _____?
5. I am going camping with Tom. (对画线部分提问)
_____ are _____ going camping _____?
奥氏体不锈钢焊接时产生热裂纹的原因之一是（）等元素形成低熔点共晶杂质偏析比较严重。
A.碳
B.锰
C.硅
D.硫
E.磷
F.镍
