题目

水、金属和化石燃料等都是宝贵的自然资源，需要珍视．请回答问题． （1） 请指出“自来水厂净水过程”中所用到的一种化学试剂及其作用． （2） 保护金属资源的有效途径有哪些？（至少2点） （3） 充分燃烧可节约化石燃料．请指出哪些因素能使燃料充分燃烧？（至少2点） 答案：明矾，用来吸附沉降，用活性炭来吸附色素和异味，通入氯气来杀菌消毒 防止金属腐蚀、回收利用废旧金属、合理有效地开采矿物，以及寻找金属代用品等 燃烧时要有足够的空气，燃料与空气由足够大的面积．8、I think we should try to find a happy memory, something to lift us on those unpleasant days．I'm saying this because I think I have just found mine．        I had some work in Glasgow then．I was on a really   1   schedule, which meant I would have no time for myself all day．I was having one of those days, when the train was completely _2 and the conversation around me seemed to be particularly   3 ．Besides, I had a bit of headache． 4_ quickly across the station hall, I fished some   5   from my pocket．There was usually someone at the exit   6   the Big Issue （a magazine that helps homeless folk earn a living）．        7   the crowd parted ways at the bottom of the hall, I saw someone selling the Big Issue．She really looked like she had been sleeping   8 ．Her clothes were   9   and she obviously hadn't had a scrub （擦洗） for quite a while．        As I   10   the exit, I saw that she was also  11   from side to side．At first I thought she was trying to keep   12   against the biting wind．But she wasn't．She was moving in time to a 13 ．I couldn't hear her, but I could see her lips moving．        When I got closer, I saw a white   14   hanging from her elbow and noticed that she had sunken eyes．She was   15 , dirty and living on the streets．I came closer and through the  16 of the traffic I could hear her  17   the immortal （不朽的） line, "．．．And I think to myself, what a wonderful world!"        I bought her last magazine for twice what I had originally   18 ．She thanked me and 19 her belongings and went tapping off along the pavement—still singing．        So, I have my happy 20 for that day, and I think it will stay with me a long, long time. 1．A．enjoyable               B．relaxing               C．tight                    D．tiring 2．A．crowded               B．delayed                C．loaded                 D．crashed 3．A．moving                 B．interesting            C．pleasing               D．meaningless 4．A．Fleeing                  B．Walking               C．Wandering           D．Searching 5．A．cigarettes              B．sweets                C．change                D．paper 6．A．selling                   B．buying                C．collecting            D．delivering 7．A．With                     B．Since                  C．Until                   D．As 8．A．comfortably          B．rough                  C．soundly               D．anxiously 9．A．shabby                  B．casual                 C．tidy                     D．fashionable 10．A．left                     B．passed                 C．approached          D．examined 11．A．jumping               B．climbing              C．rolling                 D．rocking 12．A．active                  B．energetic             C．warm                  D．awake 13．A．dance                  B．tune                    C．step                    D．sound 14．A．issue                   B．arm                     C．stick                   D．log 15．A．deaf                    B．lame                    C．mad                    D．blind 16．A．noise                   B．music                  C．voice                  D．Sound 17．A．recite                  B．compose             C．read                    D．sing 18．A．expected             B．charged               C．intended              D．organized 19．A．picked up            B．threw away         C．turned out           D．hid away 20．A．decision           B．memory                C．program            D．design 评卷人 得分 二、选择题 （每空？ 分，共？ 分）