今天我们带大家来看一下

这一道高频RA新题：

应同学们要求，每一段RA都加了背景知识帮助大家更好地记忆和消化噢~

life expectancy

Life expectancy has increased dramatically in the last century. Most people these days will live for over 70 years. This is more than double the lifespan of the average human in the seventeenth century. We can attribute our longevity to advances in medicine and lifestyle. While everyone agrees that living longer is wonderful, overpopulation is becoming a serious environmental concern.

请同学们首先注意容易读错的生词和音标：

Expectancy [ɪk'spɛktənsi]

Lifespan  ['laɪfspæn]

Attribute [əˈtrɪbjut]

Longevity [lɔn'dʒɛvəti]

正确的RA断句及重音：

Life expectancy has increased dramatically in the last century. / Most people these days / will live for over 70 years. / This is more than double the lifespan of the average human / in the seventeenth century. // We can attribute our longevity to advances in medicine and lifestyle. / While everyone agrees / that living longer is wonderful, / overpopulation is becoming a serious environmental concern.

来听一下Stephii的语音解析：