parasitic ciliate

例句：

1. 1. Parasites cancause serious health problems in their hosts.
   寄生虫可以在宿主体内引起严重的健康问题。
2. 2. Theparasites are responsible for the death ofmany people every year.
   这些寄生虫每年导致许多人死亡。
3. 3. The parasites have adapted tothe new environment and are thriving.
   这些寄生虫已经适应了新环境并正在繁荣发展。