This has meant a disaster for health and social protection in the many countries where most labour is concentrated in the informal sector and the tax base is small.
在多数劳动力集中于非正式部门以及税基较小的许多国家，卫生和社会保护工作陷入困境。
2
Currently, it is the largest concentrated continuous base in the country that is equipped with the cutting-edge Israeli water-saving irrigation technologies.
是国内目前最大的采用以色列先进节水灌溉技术的集中连片基地。
3
Cixi concentrated on centralizing her own power base.