There are many means of transportation in the world,For example ：trains,cars,planes and boats.These ways are convenient and not very expensive.But I like riding a bike.
Bicycle is a common means of transport in the world.Riding bike can help you（1） to keep health and （2）building muscle.Over-weight people can lose their weight by riding bikes.And it is important that riding bicycle is green and （3）do not pollute the air .When we travel by bike,we can breathe （4）fresh air,enjoy the beauty of the surroundings,（5）forget all the problems.Students should go to school by bikes;（6） it can have no traffic jam and would not be late for class
Please（7） slow cycling,avoid traffic accidents,and ensure the safety of life
That's why I like riding bike.I ride to school everyday,it makes me healthy.
第一个地方,help后面一般跟动词原形吧.第二个地方and后面跟的动词应该和第一个保持一致,用原形build.第三个地方,主语是it 用单数,does.第四个地方加个the吧,表示泛指.第五个地方,加个and吧,连续三个东西,一半是第三个前加个and表示并列.第六个地方,这句话你想表达的意思很清楚,就是句子有点问题.可以改为it does not cause the traffic jams ,so you would not be late for class.第七个地方.用祈使句的话,可以please be slow when riding.
暂时能看出这些,希望高手继续补充或者纠正