basic reproduction rate

例句：

1. 1.The basic reproduction rate of a virus isthe number of new infections it causes perunit time.
   病毒的基本繁殖率是单位时间内引起的新感染数。
2. 2. Thebasic reproduction rate of adisease is the average number ofpeople that contract the disease in apopulation.
   疾病的基线繁殖率是在一个人群中平均有多少人感染该疾病。
3. 3. The basicreproduction rate of a species is the averagenumber of offspring produced by a singlefemale.
   一个物种的基本繁殖率是单个雌性产生的平均后代数量。