Stephenusedtoworkinacompany.Unluckily,hegotseriousheart...
問題詳情：Stephenusedtoworkinacompany.Unluckily,hegotseriousheartdisease.Hecouldn'tworkforalongtime.Thinkinghecouldstilldosomethingforothers,hedecidedtobeavolunteer(志願者)ataChildren'sHospital.Stephe...