Bus was an important mode of transportation for Chinese people. In recent years, because the number of private cars has been increasing, the problem of traffic in cities has been more and more serious. To encourage more people to go out by bus, many cities have been trying hard to improve the quality of bus service. The equipment of buses is continually updating, and the speed of buses has been significantly improved too. However, the price of bus tickets is still very low. Nowadays, in many big cities, many local old people can take buses for free.
Bus used to be a main mode of transportation for Chinese people. In recent years, with the mounting number of private cars, the transportation issue in cities is becoming increasingly severe. Many cites have been making their efforts to improve the bus service in order to encourage more people to take buses when going out. The facilities of buses are updating continually. The speed is significantly improved as well. Nevertheless, bus fares are still quite low. Nowadays, local senior citizens in most cities are eligible for free bus rides.
词汇方面，交通工具的表达比较恰当的表达是mode of transportation，翻译成“traffic tool”其实并不是很妥当。“设施”一词的对应翻译“facility”如果不容易想到，可以选择更容易些的equipment。
句子方面，首句“公交车曾是中国人出行的主要交通工具。”如果想不到“used to be”这样比较地道的表达，简化版表达“Bus was an important…”想到大胆地使用出来。
长句“许多城市为了鼓励更多人乘坐公交车出行，一直在努力改善公交车的服务质量。”可以选择嵌套进一些词组（in order to）与从句(when going out)来丰富句式，争取高分，同样地，希望稳扎稳打的同学选用“To encourage…many cites have….”也是个不错的主意。