Have you ever seen a solar panel（太阳能电池板）in your neighborhood？Solar panels take energy from the sun and turn it into electricity.Over the past ten years，the price of solar panels has gone down greatly.In many parts of the world，solar energy is now the cheapest form of electricity.More and more people have started using solar energy to power their homes.
   However，solar panels also have their problems.They stop working at night and on rainy days.Is it possible to make them produce electricity all of the time？
   Scientists at Suzhou University，China，have invented a new solar panel now.It can produce electricity not only from solar energy but also from falling rain.When a raindrop falls on the solar panel and then rolls（滚动）down，it creates friction（摩擦力）on the surface of the panel，which can then be turned into electricity.
   Sun Baoquan is one of the inventors. "Our new invention can produce electricity in any weather during the day，" he says. "It can even provide electricity at night if there is rain. "
   The solar panel，however，does not make much electricity from falling rain.So Sun Baoquan is still working hard to improve it.The scientist also wants to make solar panels more flexible，which are as soft as clothing.
   The field of solar energy is developing fast.Scientists around the world have been improving solar panels.Some have been working on ways to join solar panels and wind power together.Some have been trying to use sunlight to produce liquid and gas fuels（液体和气体燃料）.

（1）Which energy is now the cheapest form of electricity in many parts of the world？

A

A

A．Solar energy.
B．Nuclear energy .
C．Wind energy.
D．Water energy.
（2）What is one of the problems of common solar panels？

B

B

A．The price of them is rising.
B．They can't work all of the time.
C．The solar panel will roll down when it rains.
D．They can hardly power people's homes.
（3）Why is the new solar panel more scientific and useful？

D

D

A．It was invented by Sun Baoquan.
B．It has a larger size than a common one.
C．It produces more electricity from falling rain than solar energy.
D．It can produce electricity day and night and even in rainy conditions.
（4）What does the underlined word "flexible" mean in Paragraph 5？

A

A

A．柔软的
B．光滑的
C．坚硬的
D．灵活的
（5）We can infer（推断）from this text that

B

B

.
A．there is no room for developing solar energy
B．there is no end to the research in the field of solar energy
C．solar energy has completely taken the place of other kinds of energy
D．solar energy is not the best energy we use in the cities