题目

用括号中所给单词的适当形式完成下列句子，每空格限填一词 1.Mum sometimes _______ me how to do the housework on Sundays. (teacher) 2.We also call the people from England ________ . (Britain) 3.Jack slammed(砰地关上) the door ________ after he was laughed at. (angry) 4.It’s really ________ for a child of five to take care of himself. (possible) 5.Children are educated to be_______ when they are very young. (honesty) 6.Sichuan Earthquake is China’s biggest ________ disaster since 1949.(nature) 7.WHO is the short form of the World Health _________. (organiz著名化学家徐光宪获得国家最高科学技术奖，以表彰他在稀土萃取理论方面作出的贡献．已知：金属铈（稀土元素）在空气中易氧化变暗，受热时燃烧，遇水很快反应．（注：铈常见的化合价为+3和+4，氧化性：Ce4+＞Fe3+＞I2．）下列说法正确的是（　　）A．铈溶于氢碘酸的化学方程式可表示为：Ce+4HI 高温 . CeI4+2H2↑B．用Ce（SO4）2溶液滴定硫酸亚铁溶液，其离子方程式为：Ce4++2Fe2+═Ce3++2Fe3+C．在一定条件下，电解熔融状态的CeO2制Ce，在阴极获得铈D．四种核素13658Ce、13858Ce、14058Ce、14258Ce，它们互称为同素异形体