Siphonales

例句：

1. 1. The parasite is causing the host to suffer greatly.
   这种寄生虫正在使宿主遭受极大的痛苦。
2. 2. Parasites can be harmful to both the host and the environment.
   寄生虫对宿主和环境都可能有害。
3. 3. The parasite was discovered by a veterinarian who treated the infected dog.
   一位兽医发现了这种寄生虫，并治疗了感染该犬的狗。