They're just a bunch of leeches cadging off others!他们只不过是一帮伸手向人要这要那的寄生虫！Broussais was the first physician to use leeches as a cure-all.布鲁赛是第一个把水蛭当成万灵药的医生。A heavy infestation of small leeches on the eyeballs caused the blindness of the bird.大量小蛭虫在眼球上聚集寄生使这鸟双目失明。