第一个五年计划的中心环节是优先发展重工业。而机器制造工业是重工业的心脏。我们知道,为了发展工业和农业生产,为了发展交通运输业,为了建立现代化的国防,需要各种机器装备——机床、采矿冶金设备、发电设备,化工机械、纺织机械、拖拉机、联合收割机、飞机、火车、轮船以及大炮、坦克等等。没有机器制造工业,就不可能进行大规模的建设。各种机器装备都是主要地由钢、铁、铜、铅、锡等各种金属材料制造出来的。没有金属村料,我们就不可能有机器制造工业,大量金属材料的供应是发展机器制造工业的基本条件。因此,发展冶金工业,供应各种各样的金属材料,也就有了首要的意义。什么是有色金属 The central part of the first five-year plan is to give priority to the development of heavy industry. The machine-building industry is the heart of heavy industry. We know that in order to develop industrial and agricultural production, in order to develop the transportation industry, and to establish modernized national defense, various types of machinery and equipment are needed—machine tools, mining and metallurgical equipment, power generation equipment, chemical machinery, textile machinery, tractors, and combine harvesters. Airplanes, trains, ships, artillery, tanks, etc. Without the machine-building industry, it is impossible to carry out large-scale construction. All kinds of machinery and equipment are mainly made of various metal materials such as steel, iron, copper, lead and tin. Without metal materials, we cannot have a machine manufacturing industry. The supply of a large amount of metal materials is the basic condition for the development of the machine-building industry. Therefore, the development of the metallurgical industry and the supply of all kinds of metal materials are of primary importance. What is non-ferrous metal