Heavy semi-trailer tractor belongs to trailer, that is, tractor, which requires driver's license above A2. In addition, the heavy-duty semi-trailer tractor belongs to the heavy-duty truck when the violation is inquired. Conditions for applying for A2 driver's license: You must hold the driving qualification of "B 1 medium-sized bus" or "B2 large truck" for more than three years, and there is no record of full marks before application in the last two consecutive scoring cycles; Or have obtained the qualification of "A 1 Bus" for more than one year, and there is no record of full marks before application in the latest scoring cycle; Drivers aged 24-50 and above may, under normal circumstances, apply to the vehicle management office of their place of residence for a replacement driver's license. Heavy-duty semi-trailer tractors belong to heavy trucks when inquiring about violations. Traffic violation inquiry refers to the inquiry of motor vehicles, non-motor vehicle drivers and pedestrians who violate the road traffic safety law and traffic management regulations. Traffic violation inquiry refers to the behavior of inquiring about violations of traffic management by motor vehicles, non-motor vehicle drivers and pedestrians through SMS, telephone and internet. There are five ways to inquire about motor vehicle violation: terminal inquiry of traffic brigade, service website inquiry, telephone inquiry, mobile phone inquiry and tool inquiry.