案例:曾强是北京某物业小区的保安员,来北京打工不到两年半。期间曾做过建筑工人和送水工。无论是做哪种工作,用人单位从未与曾强签过任何劳动 Case: Zeng Qiang, a property security officer in Beijing, came to work in Beijing for less than two and a half years. During this period have been construction workers and plumbers. No matter what kind of work to do, the employer has never signed any work with Zeng Qiang