摘要：Bicycles, or bikes, are a fun and low-cost way to travel. There are more bikes in the world than cars. They come in all sizes and

Bicycles, or bikes, are a fun and low-cost way to travel. There are more bikes in the world than cars. They come in all sizes and have many uses. Bike designs have changed over time. However, all bikes still need two wheels and a frame. A bikerider is called a cyclist.

自行车，又称单车，是一种有趣且低成本的出行方式。全世界的自行车数量比汽车还多。它们有各种尺寸，用途广泛。虽然自行车的设计随着时间不断演变，但始终离不开两个车轮和一个车架。骑车的人被称为“骑行者”。

The first bicycle was made in 1817, but it did not have pedals. The riders had to push it with their feet. By 1868 the velocipede was a type of bike with a new part: pedals. Over time more parts were added, like a chain, brakes, and soft tires.

第一辆自行车诞生于1817年，但它没有踏板，骑行者需要用脚蹬地前进。到了1868年，一种叫“velocipede”的自行车出现了，它新增了踏板。随着时间推移，陆续加上了链条、刹车和充气轮胎等部件。

People also added baskets to haul cargo and food. Bike bells say "hello" and warn people that a bike is coming. By the 1890's, bicycles were very popular. People formed clubs and held races. Many people could afford bikes, and this helped sales. The Wright brothers owned a bike shop. They used some of their bike parts to build the first airplane.

人们还在车上加装篮子，用来运送货物和食物。车铃不仅用来打招呼，也提醒路人自行车正在靠近。到19世纪90年代，自行车已非常流行。人们组建俱乐部、举办比赛。由于价格亲民，自行车销量节节攀升。莱特兄弟曾经营自行车店，他们还用部分自行车零件造出了第一架飞机。

Today, bikes have changed once again. Carbon fiber is used instead of metal. The carbon fiber is light and strong. A folding bike lets riders put a bike into a car or train. Electric bikes let riders go faster with less effort. These e-bikes run on a battery motor. The small motor hides inside the bike.

E-bikes are becoming more popular.

如今，自行车再次升级：碳纤维取代金属材料，兼顾轻量化与高强度；折叠车能轻松放进汽车或带上火车；电动车则让骑行更省力，靠电池驱动的小电机藏在车身内部，正越来越受欢迎。

Today, bikes are used for work by different people. Many people in the world can afford to buy a bike. Some cities have special lanes for bikes on the road. In some places, a bike is quicker than a car. Bikes are also good for exercise and fun for families.

现在，不同职业的人把自行车当工具。全球多数人都能负担其价格。不少城市设有自行车专用道，在某些地方，骑车甚至比开车更快。它既是家庭娱乐方式，更是健康运动的绝佳选择。

来源：昊天教育