我国文献机构目录传统上有四种，目录他们是按______标准来划分的。
参考答案：文献检索途径
液体沸腾时，必须具备两个条件：温度达到 ，且继续 热，液体沸腾的特点是：吸收热量但温度 。
He has been ______to general manager because of his excellent work in the company.
A．proposed
B．produced
C．promoted
D．programmed
