Commercial vehicles are divided into three categories: passenger cars, vans and semi-trailer tractors. The passenger bus subdivided into small passenger car, city bus, coach, tourist bus, hinged passenger bus, coach, off-road bus, private bus. Goods vehicles are subdivided into general goods vehicles, multi-purpose lorries, full trailer tractors, off-road trucks, special operations vehicles and special goods vehicles. The selection and evaluation of transactions. Engaging in foreign exchange investment, one must choose a profitable trading method. Here are some factors to consider in trading options. Gasoline English called Gasoline (beauty)/Petrol (UK), appearance is transparent liquid, inflammable, distillation range of 30 ℃ to 220 ℃, main components in C5 ~ C12 fatty hydrocarbon and naphthene classes, and aromatic hydrocarbon, certain amount of Gasoline with high octane number (antiknock combustion performance), and by the discretion of octane number can be divided into no. 90, no. 93, no. 95, no. 97. Straight-run gasoline components which are obtained by oil refining gasoline, catalytic cracking gasoline, catalytic reforming gasoline components such as different after refined gasoline with high octane number components made by the harmonic, mainly used in automobile ignition internal combustion engine fuel. Ť he returned to the top five-year bond, because record lows in January has significantly improved, now pay 22 PC more than the beginning of the year.