#trailer_truck__trailertruck__tractor_trailer__trucking_rig__articulated_lorry__semi  a truck consisting of a tractor and trailer together
  supertype:  truck__motortruck  an automotive vehicle suitable for hauling
  subtype:  tandem_trailer  trucking rig with two trailers in tandem
  part:  semitrailer__semi  a trailer having wheels only in the rear; the front is supported by the towing vehicle
  part:  trailer  a large transport conveyance designed to be pulled by a truck or tractor

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