To drive less is the environment.

— Sure. But you ________________ return it after class.

— Let me think... We need three apples.

Shall we make Mike our monitor? He is honest responsible.

    Day a man found a cocoon (茧) of a butterfly in the forest. He sat there for several hours and watched the butterfly. Suddenly a small opening appeared, and the butterfly made its great effort to force its body through that little hole. Then it seemed to stop making any progress. It appeared as if it had gotten as far as it could and it could go no further.

    So the man decided to help the butterfly. He cut off the remaining bit of the cocoon so that the butterfly could come our easily. But to his surprise, the butterfly got a heavy body and very small wings when it came out of the cocoon.

    The man continued to watch the butterfly because he expected that the body would grow smaller at any moment and the wings would become larger and be able to fly. But neither happened! In fact, the butterfly spent the rest of its life crawling (爬) around with a heavy body and small wings. It was never bale to fly.

    The man was in his kindness, but he did not understand the nature rules. Before the butterfly came out of the cocoon, fluid (流体) from its body must be forced into its wings, and then it would be ready for flying. It must have a hard struggle (拼搏) to get through the small opening to get its freedom from the cocoon.

    Sometimes struggles are exactly what we need in our life. If God allowed us to go through our life without any difficulties, it would make us fail. We would not be as strong as we could have been; we could never fly.

    People burn coal, gas and oil to get energy But there are problems with these fuels (燃料). (A)________, these fuels cause pollution. Pollution makes the air and water unsafe for humans. Secondly, these fuels will not last forever. One day, we will run out of these fuels.

    Scientists are looking for new kinds of energy. One is heat from the Earth. We know that (B)地球中央非常热. We cannot reach the center of the Earth, but in some places the heat from the Earth's center comes to the surface of the Earth. Perhaps you know about some of these places One place is volcanoes (火山). It is very dangerous to go near an active volcano, (C) _______ we cannot use the energy from this.

    Another kind of heat from the Earth is hot springs (温泉). In these places, hot water comes to the surface of the Earth. If this water is near a town, the hot water can be sent in pipes (管道) directly to people's houses to heat them .In Iceland, this is a common way to heat houses.

    (D)In Australia, scientists are looking for ways to make energy using hot rocks under the surface of the Earth. They want to pump (抽水)water onto the hot rocks .When the water hits the rocks, it makes stream(蒸汽). The steam is piped to power stations where (E) it is used to make electricity. The electricity can then be sent all over the country.