parasitic habit

例句：

1. 1. Parasites can cause 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.The parasite's life cycle is complex and requires a specific host.
   这种寄生虫的生活周期复杂，需要特定的宿主。
3. 3. The parasite spreads quickly through the population, causing widespread disease.
   这种寄生虫通过人群迅速传播，导致广泛的疾病。