Reading comprehension: Choose the best topic from A to F according to the meaning of each paragraph. No one knows when the first house was built and who was the first one to built the house. But the houses are changing all the time. (     )1. What will the house of the future look like? Could it have gardens on its walls, or a pool with fish for dinner? Architects (建筑学家) believe that they may come true one day. The only thing for sure is the houses will be as green as possible in the future. (     )2. Many architects in the world would like to build a house like a leaf, the surface of the house collects sunlight during the day. The energy can be used to heat water, produce electricity, and even make fresh air for the room. The'root'(根) of the house is deep under the ground. It uses the soil to control the room's temperature. (     )3. Like a lizard (蜥蜴), changing color with the weather is the most important design of a lizard house. When it's in the bright sun, the cover of the house will turn white to protect it from strong heat. During dark days, it turns dark and takes in as much light and heat as possible to produce energy. (     )4. This design is perhaps for the future of food. It has a garden on the outside wall of the house. People can plant tomatoes, carrots and green tea on them. So every morning, you just need to walk outside and collect your meals. (     )5. Looking to the future isn't the only way to be green. Sometimes, the old ways of building houses can also help cut down energy use. For example, a chimney (烟囱) can be a useful air conditioner because it is easier for hot air to run out of the chimney. A. Learning from the past                             B. Meals at home C. The lizard house                                      D. Houses in the future E. The tree house                                         F. The history of the houses