knowndoctorinLondonJ的精選

問題詳情：Asawell-knowndoctorinLondon,JohnSnowwaswillingtohelpordinarypeople  61  (expose)tocholera（霍亂）.Heknewthatonlywhen  62  causeofitwasfoundcouldthe  63 (dead)diseasebecontrolled.Hehastw...