题目

阅读下面短文，从短文后各题所给的A、B、C和D四个选项中，选出可以填入空白处的最佳选项。 Forcenturies, Beijing has been one of China's most important cities. 1 a place for emperors and officials, today itis an international city and a popular tourist2. People fromall over the country are moving to Beijing to 3 jobs and opportunities as this exciting cityis a place where dreams can come true. Throughout the city, 4 dressed business people 5 for their offices, mobile phones held to theirears and visitors can only watch and imagine the deals and 6 being made at各种形式的能之间可以在一定的条件下相互转化，请按表中示例完成表格．能量转化实     例化学能转化为电能干电池对外供电    用电熨斗熨衣服机械能转化为内能