For example, China is divided into three types of gasoline, unleaded gasoline, ethanol, gasoline, methanol petrol, unleaded petrol is also divided into three categories, the four, the third, second.

• 比如，我国目前汽油分为三类，无铅汽油，乙醇汽油，甲醇汽油，无铅汽油也分为三类，国四、国三、国二。