President Barack Obama claimed progress Wednesday in his second-term drive to combat climate change but said more must be done to address a generational problem. One year after unveiling an aggressive plan, Obama said new【C1】______limits on power plants, renewable energy projects and new【C2】______for green technology have cleared the way for further action in the U.S. and abroad, despite steadfast【C3】______from much of Congress. "When you take those first steps, even if they"re【C4】______, and even if there are politics sometimes, you start【C5】______momentum and you start mobilizing larger and larger communities," Obama said. Obama"s【C6】______served as a progress report for his climate plan, which the president【C7】______out last June. Twelve months later, much of the plan is in【C8】______although the most ambitious steps are still up in the air and will take years to be【C9】______realized. Change won"t be instantaneous, Obama【C10】______. "There"s no silver bullet." Indeed, many of the steps he"s taking are【C11】______, limited in scope by hostility from both parties to putting a【C12】______on carbon pollution, which would require new laws from Congress. Still, Obama said he"s seeking to【C13】______the problem but cutting it up into smaller pieces. "We"re moving, and it"s making a【C14】______," he told a supportive crowd at the League of Conservation Voter"s annual dinner. The environmental group【C15】______Obama early in his 2008 campaign.【C16】______on the international front, momentum has been obscure.【C17】______global climate talks next year in Paris, there are fresh【C18】______that some countries are urging others to resist【C19】______moves to curb carbon. That could discourage even bigger polluters from【C20】______.
【答案解析】解析：此处需要一个名词表示政府对绿色技术的态度。下文提及此三项措施为采取进一步行动扫清了道路(dear the way for further action)。绿色技术不会对环境造成危害，因此，如果要推动进一步的(减缓气候变化)计划，绿色技术应该受到政府的推崇。因此，答案为A项incentives“鼓励；刺激”。
单选题
【C3】
【正确答案】
D
【答案解析】解析：空格前有despite“不管”，由此推断其与上文的积极语义(dear the way for further action)相对。且下文第6段提及来自两个政党的敌意(hostility from both parties)。两个政党均对奥巴马的计划有敌意，由此推断他的计划遭到反对，故选D项opposition“反对”。
单选题
【C4】
【正确答案】
B
【答案解析】解析：本句强调只要我们迈出第一步，就能收获积极的回报(you start mobilizing larger and larger communities)。句中插入even if引导的让步状语从句。even if常用来强调尽管会有些阻碍，事情还是会照样发展的。因此，even if从句中的内容是对积极结果的一种阻碍，故选B项hard“困难的”。
【答案解析】解析：此处需要一个词组表达总统在去年6月份所做之事。下句紧接着提及过了12个月后，他的计划的实施情况，Twelve months later呼应了上文的one year after unveiling all aggressive plan“在公布了一项大胆计划的一年后”。由此可知，此处动词应与unveil表达之意相近，lay out“提出；展示”符合要求，故选D。
单选题
【C8】
【正确答案】
B
【答案解析】解析：根据句中表达让步和转折的although可推断，句中表示奥巴马计划完成情况的两个短语be in______ 与be in the air具有相反的语义。be in the air表示“未定的，悬而未决的”，be in motion“在运行中”符合要求，故选B。
单选题
【C9】
【正确答案】
A
【答案解析】解析：此题需要一个修饰realized的副词，realized的主语是the most ambitious steps。该句前半句提到much of the plan is in motion，即部分计划已经进入启动阶段，后半句又提及还有一些计划和步骤在等待实施中(the most ambitious steps are still up in the air)。该句讲述的是整个计划实施的程度及时间顺序。fully realized表示“完整实施”，与此处语境相符，故选A。
单选题
【C10】
【正确答案】
C
【答案解析】解析：空格前后均为否定表达：Changes won"t be instantaneous“改变不会一蹴而就”和There is no silver bullet“没有特效办法”。由此推断此处是奥巴马提出需要认清、或者需要提醒公众意识到的问题。对比其他选项，C项的cautioned“警告”最为合适。
单选题
【C11】
【正确答案】
D
【答案解析】解析：空格后的非谓语动词短语limited in scope作状语对主句进行补充说明：此计划在范围上受到局限，由此推断整个计划的步骤不是很激进，而是较为温和的。因此应选D项modest“适度的”。
单选题
【C12】
【正确答案】
B
【答案解析】解析：上文提及奥巴马的计划是通过很多手段(limits on power plant, renewable energy projects，green technology)来应对气候变化。这些手段都是对环境有好处的。carbon pollution对环境有害，因此，奥巴马采取的措施应是对这种破坏环境的行为进行惩罚。因此应选B项，put a price on carbon pollution意为“让排碳污染环境的人付出代价”。
【答案解析】解析：上文多次提及奥巴马有关环境的计划已经取得了进步(claimed progress，progress report, We are moving)，而下文提及momentum has been obscure“势头已经很难见到了”。因此，两部分之间的逻辑关系应为转折，答案为转折连词Yet，故选D。