京城边上的小四轮●安静小四轮，是各类小型拖拉机的简称。其实在广义上，这种小四轮的范畴还应包括三轮机动车。它们共有的特性是烧柴油，机动灵活，载重能力强。但因其构造简单，污染严重，制动效果及其它功能相对较差。特别是它的噪音“嘟嘟”发出的声响早已令人侧目。... Small four-wheeled on the edge of the capital ● Quiet little four, all kinds of small tractors referred to. In fact, in a broad sense, such a small four-wheeled category should also include three-wheeled motor vehicles. Their common feature is burning diesel, flexible, load capacity. However, due to its simple structure, serious pollution, braking effect and other functions are relatively poor. In particular, its noise “toot” sound has long been striking. ...