Yet it is hard to imagine that the merger of a few oil firms today could re-create the same threats to competition that were feared nearly a century ago in the U.S., when the Standard Oil Trust was broken up.（Text4. 2001）
merger / ˈmə:dʒə(r) / n.(机构或企业的)合并，归并
firm / fə:m / n.公司；商行；商号
threat / θret / n.威胁；恐吓
fear / fiə(r) / v.害怕；畏惧
break up 破碎；结束；解散
结构分析（图片可点击放大）
翻译
不过，很难想象如今几家石油公司的兼并会再次对竞争构成近100年前美国人担心的那种威胁，那时标准石油托拉斯被迫解体。
你需要知道
when the Standard Oil Trust was broken up是定语从句，修饰nearly a century ago，when为关系副词。若把它理解为时间状语对理解句子含义无影响，不需要深入区分哦。
预告明日长难句
A lateral move that hurt my pride and blocked my professional progress prompted me to abandon my relatively high profile career although, in the manner of a disgraced government minister, I covered my exit by claiming “I wanted to spend more time with my family”.（Text5. 2001）
