It is a rainy (阴雨的) day. A train stops at a small {#blank#}1{#/blank#}. A man is on the train and he feels hungry (饥饿的). He looks out of the window (窗) and sees a shop. A woman is {#blank#}2{#/blank#} cakes in the shop and the cakes look {#blank#}3{#/blank#}. The man wants to {#blank#}4{#/blank#} a cake, but the shop is a little (有点) {#blank#}5{#/blank#} from the train. The man doesn't want to walk in the rain. Then he sees a boy. The boy is about five {#blank#}6{#/blank#} old. He's playing near the window. "Come here, boy!" says the man, "Do you know how {#blank#}7{#/blank#} the cake is?" "One dollar for one." says the boy. The man gives the boy two dollars and asks him to buy {#blank#}8{#/blank#} cakes. "One is for you and the {#blank#}9{#/blank#} is for me," he says to the boy.

    After some time, the boy comes back. He's eating a cake. He {#blank#}10{#/blank#} the man one dollar. "Sorry, there is only one cake left (剩余). I eat the cake and here is one dollar back," says the boy.

Joan: Daddy, do you have any  {#blank#}1{#/blank#} this Saturday?

Dad: I am sorry. I have {#blank#}2{#/blank#}things to do.

Joan: I want to go to fly a kite. I do hope you can play with me for one hour or two hours.

Dad: I {#blank#}3{#/blank#} to go with you, but I must work and do some shopping for grandparents.

Joan: Oh, I see.{#blank#}4{#/blank#} this Sunday? Can you fly kites with me then?

Dad: {#blank#}5{#/blank#} . That's a good idea.

Joan: Great!

    Free energy is everywhere around us. There are many ways to make and collect energy from{#blank#}1{#/blank#}sources(来源) like sun, wind, water, etc. But people always make things difficult by not using these sources of energy. In the last few years there have been a great number of new ideas for generating(产生) energy. People suddenly realized that everyday things can be a source of energy, such as riding a bike, running or just{#blank#}2{#/blank#}, etc. But, is there anything else that can be used for collecting energy? We{#blank#}3{#/blank#}have to change our way of thinking if we want to change the world.

    So comes the idea of solar( 太阳能) roadways. Are they the road of future? Why don't we use them for collecting energy?

    The US Department of Transportation{#blank#}4{#/blank#}$100,000 to Solar Roadways to build the first ever Solar Road.