kē xué jiā / tōng guò / yán jiū / dì sì jì / de / chén jī wù / lái / liǎo jiě / gǔ qì hòu / de / biàn huà科学家通过研究第四纪的沉积物来了解古气候的变化。Scientists study Quaternary sediments to understand past climate changes.