Unemployment is a complex social and economic issue, and is also a kind of representation of the deviation between the labor force and the productivematerial.
失业是一个复杂的社会经济 问题，是劳动力与生产资料相脱离的一种表征。
2
As a kind of productivematerial, every type of engineering machine has no monopoly market structure, and the approximator and replacer are emerging in endlessly.
工程机械作为一种生产资料，各个机种均不具有垄断性的市场结构，近似品、替代品层出不穷。
3
Being the uppermost productivematerial and the most direct object for farmers, cultivated land is one of the basic factors consisting of the comprehensive ability of crop production.