社会工作得以发生的基本前提是()。
Thefirstpaperwasmadefromthebarkofthemulberrytree.
InthenortheasternUnitedStates,itrainsintermittently间歇地throughoutthespring.
Unliketraditionalgyms,app-backedgymsofferpeople___________optionstoexercise.
TheNativeAmericaninterpreterSacajaweawasavaluablememberoftheLewisanddarkexpeditionin1805.
