268.[答案]B. taken up.[注释]take up开始从事。take on参阅Ⅲ，162,171注释。hold on, hold up参阅Ⅲ，162,171注释。

267.[答案]D. exclusive.[注释]exclusive(=reserved to the person(s) concerned)独有的;This bathroom is for the president's exclusive use.eventual最终的;versatile通用的，万用的;extensive广泛的。

266.[答案]C. resemblance.[注释]resemblance n. 像(to)。 resemble(vt.)像; She resembles her mother.(=She takes after her mother.)imitation模仿;仿效;confusion混乱，混淆;similarity相似性。

265.[答案]B. After all.[注释]after all毕竟。

　“for all + 名词”意为“尽管”: For all his wealth, he was unhappy.(尽管他富有，但他并不幸福。)

264.[答案]B. shut out.[注释]shut out(=prevent from coming in; block)排除，排斥：They shut out our dust by having double windows.(他们用双层窗户防尘。)put out扑灭;get across越过;使人了解;come across偶然遇到。本题译文：第二次世界大战中，马耳他建立了有效的防空屏障以防止意大利和德国的轰炸机侵入。

263.[答案]B. beating.[注释]beating 此处是动名词，指“(心)跳”：Her heart was beating furiously.

262.[答案]D. consultation.[注释]consultation商议：hold a consultation with sb. about sth.(与某人商谈某事)。conference讨论会;participation参加，参与;intervention干预，干涉。

261.[答案]D. consistent.[注释]consistent 1)始终如一，前后一致：He is not consistent in his statements.(他的话并不前后一致。) 2)与......一致：The story is not consistent with the facts. What you say is not consistent with what you do.

260.[答案]A. broken through.[注释]break through(=be successful after overcoming a difficulty)突破;取得重大成果：Scientists hope to break through soon in their fight against heart disease.(科学家希望在与心脏病斗争中很快取得重大成果。)本题译文：科学家认为他们在探索某些重要疾病的病因中已取得重大突破。

259.[答案]D. chance.[注释]chance(偶然的)机会。Have与the(或 a) possibility不能搭配;常用There is a possibility for sb. to do sth.表示客观存在的“可能性”。