①保持车内空气新鲜。车厢内人多,人体代谢产物也必然多。人体中有近百种气体随呼吸排出,其中以二氧化碳排出量最多。当空气中二氧化碳浓度达到0.5%时,人就会出现头痛、头晕等不适感。加之汽车发动机器产生的一氧化碳及有些人在车上吸烟,均使车厢内空气质量下降。因此,车窗要适 ① keep the car fresh air. Many people inside the car, the body’s metabolic products are bound to be more. Nearly 100 kinds of gases in human body are exhaled with breath, of which the most is carbon dioxide. When the concentration of carbon dioxide in the air reaches 0.5%, people may experience headache, dizziness and other discomforts. Coupled with carbon monoxide generated by car engine and some people in the car smoking, all make the air quality inside the car down. Therefore, the windows should be suitable