Over the past few years, we have made dramatic breakthroughs.
2018年12月六级真题（第二套）听力 Section C
Today's battery breakthroughs come as the world looks to expand modern energy access to the billion or so people without it, while also cutting back on fuels that warm the planet.
2016年12月六级真题（第一套）阅读 Section C
柯林斯高阶英汉双解学习词典释义
N-COUNT
突破；重大进展
A breakthrough is an important development or achievement.