While the clonal selection principle is responsible for generating the memory cell population, the immune network theory prevents the population size from increasing quickly.

克隆选择用来产生抗原的记忆细胞群体，免疫网络理论则用来抑制该群体规模的快速增长。

youdao

The population on Earth is still increasing quickly.

地球上的人口仍然在快速增长。

youdao

The world's population is increasing very quickly.

世界人口正在快速增长着。

youdao

It's clear Lagos needs to quickly develop its overburdened infrastructure to accommodate the needs of a rapidly increasing population and provide jobs, education and proper infrastructure or risk significant social upheaval.

CNN: Lagos of the future: Megacity's ambitious plans