#OG10语法268题及GWD22语法总结日记十五 搜索结果
14.PaleontologistsbelievethatfragmentsofaprimatejawboneunearthedinBurmaandestimatedat40to44millionyearsoldprovideevidenceofacrucialstepalongtheevolutionarypaththatledtohumanbeings.A.at40to44millionyearsold
