疟原虫

例句：

1. 1. Malaria is a serious disease that can be transmitted by mosquitoes.
   疟疾是一种严重的疾病，可以通过蚊子传播。
2. 2. The researcher found that the malaria parasite was responsible for the disease.
   研究者发现疟原虫是这种疾病的原因。
3. 3. The patient had to take medication and rest in order to recover from malaria.
   病人需要服药并休息来治愈疟疾。