能以相同的吸收率且部分地吸收由零到∞的所有波长范围的辐射能的物体称为()。
参考答案:灰体
Our monitor, who by then ______ admission to Fudan University, decided to do some part-time jobs to gain more practical experience.
A.gained
B.was gaining
C.has gained
D.had gained
混凝泵主要用于()等场所。
A.固定点长时间作业;
B.小型工地;
C.用料点集中;
D.泵送距离及高度较大。