16.Bicycles play an important role in our daily life.(1)
As we travel around on bicycles,we might not know the long history of this amazing little machine.No one can say for sure when the bicycle was invented.(2)
They had two wheels.But that was all they had in common with the modern bike. By the middle of the 1800s,improvements were made to the early bicycles.A pedal(踏板) for moving the bicycle forward was added.(3)
Since the bicycle was made of wood,and later of metal tires,riding on the roads that aren't smooth was uncomfortable. In the late 1870s,a huge front wheel was used and the seat was moved forward so that the rider could sit directly over the front wheel and pedals.However,the rider sat up high over a huge front wheel and easily fell down.(4)
In 1885,the first successful "safety" bicycle was designed.The seat of this bike was positioned further back towards the middle of the bike.And a basic gearing(齒輪) system was added.The new design also added other important things.(5)
It solved safety matters by reducing the size of the front wheel.The rest,as they say,is history! A.We can keep happy by bike. B.With these,the safety bicycle was born. C.So it was dangerous to ride these bicycles. D.Today's bicycles are light,fast,and comfortable. E.And that allowed the rider to keep both feet on at all times. F.But early scooter-like bikes were invented in France in the late 1700s. G.Riding a bike is not as relaxing as taking a train to go out with friends.
M:I didn't get enough sleep because I studied until midnight last night. W:Oh,that's too bad for your health(2)
M:But I have three after-school classes.So I can only start studying after them. W:(3)
M:I did.But they believe it is necessary for me to get more after-school classes. W:You can ask for our head teacher's help.(4)
M:Good idea.I will ask our head teacher him for help. W:I hope my advice will work for you. M:I am sure it will.Thanks a lot. W:(5)
A.It's my pleasure. B.I don't agree with you. C.What is the matter with you ? D.Let him talk with your parents. E.You should start studying earlier. F.I played football all day yesterday. G.Why didn't you talk with your parents?