问题 选择题

声波形成到听觉形成需经过(    )

①听小骨   ②鼓膜   ③耳蜗内的听觉感受器

④外耳道 ⑤大脑皮层的听觉中枢

A.声波→①→②→③→④→⑤

B.声波→④→②→①→③→⑤

C.声波→④→①→②→③→⑤

D.声波→④→③→①→②→⑤

答案

答案:B

题目分析:听觉的形成过程如下:外界的声波经过外耳道传到鼓膜,引起鼓膜的振动;振动通过听小骨传到内耳,刺激耳蜗内的听觉感受器,产生神经冲动;神经冲动通过与听觉有关的神经传递到大脑皮层的听觉中枢,就形成了听觉.

阅读理解

Too many cars have created a lot of serious problems in our world. Besides congestion(拥塞), accidents and fast fuel consumption(消费), cars are responsible for a good part of air pollution in big cities. All the time, they are pumping huge amounts of waste gases into the atmosphere. These gases are very harmful, causing disease and even death. Last winter, car fumes(烟雾) formed heavy smog over Beijing, making the sky gloomy for weeks and deteriorating people's health.

One possible solution is to design and develop clean cars and clean fuels. In Tsinghua University, campus buses are driven by electricity. In Beijing some of the public buses begin to run on natural gas, which does not give off as much carbon dioxide as the petrol. But it may take decades for the new models of clean cars to completely replace the traditional ones.

Another solution is to develop modern public transportation systems and restrict (限制)the use of private cars. If the price of petrol rises constantly and the public vehicles(交通车辆) are efficient and convenient enough, most people will not use private cars. And the total number of cars in big cities will reduce greatly.   

On the whole, the elimination (根除)of air pollution needs the co-efforts from the government, the public and the environments. This problem will be solved only with the help of science and technology.

小题1:What is the main reason for air pollution in big cities?

A.congestion

B.accidents

C.fast fuel consumption

D.cars小题2:What is the best title of this passage?                               

A.Air Pollution and Cars

B.Air Pollution

C.the Cause of the Pollution

D.Ways to Solve the car Problem小题3:How many ways are mentioned to solve the pollution caused by cars?      

A.One

B.Two

C.Three

D.Four小题4:Which of the following is TRUE according to the passage?               

A.New models of clean cars will soon replace the traditional cars

B.Public transportation should replace all the private cars

C.In some university, electricity is used in school buses

D.It is only the government’s efforts that can help solve air pollution caused by cars

单项选择题