报刊剪辑分析：是科研人员从与课题相关的各种报刊杂志上所刊登的文章、报导中，分析和收集信息。
参考答案：对
The steel works in which David has worked for five years us with raw material in large quantities in the past two years. [ ]
A.has been supplying
B.was supplying
C.have been supplying
D.were supplying
有一条主芯线截面积为70平方毫米的矿用橡套电缆，长时间允许电流为（）安培。
A.113
B.138
C.173
D.215
