Energy is very important in our modern life. People use energy (5)__________ transportation, cooking, heating and cooling rooms, manufacturing, lighting, and entertainment. (6) __________ energy nowadays comes from fossil fuels – petroleum, coal, and natural gas. (7) __________, burning fossil fuels causes pollution. Also, if we don’t find new kinds of energy, we will (8) __________ all the fossil fuels in the near future. 5. A. in      B. for      C. at      D. by 6. A. Most      B. Mostly      C. almost      D. Utmost 7. A Because      B. Moreover      C. Therefore      D. However 8. A. use up      B. run on      C. take over      D. cut off