一对一指导 月收入破万

简介：In contrast, the hydraulic blower in the West appeared very late, almost four to five hundred years later than China, but the hydraulic hammer and forging machine appeared more than a hundred years ago. The reason for this is that in addition to the small number of fine armor requirements in ancient Chinese society and sufficient manpower to complete it, there are also reasons why craftsmen are not valued and technology research and development is suppressed.