Complex sentence: A jeep train usually refers to a railway train hauled by a rail jeep, Jeeps were converted from road vehicles into steel-wheeled rail switchers (shunters), light locomotives, or speeders (draisines).
Split into simpler sentences: A jeep train usually refers to a railway train hauled by a rail jeep. For this purpose, Jeeps were converted from road vehicles into steel-wheeled rail switchers (shunters), light locomotives, or speeders (draisines).