Then, something about single system memory.

介绍，然后是关于单个。

They found that people learn language using two memory systems: declarative and procedural.

他们发现人们使用两种记忆系统学习语言：陈述性和程序性。

Immunoassays, on the other hand, tap into the immune system's memory of the virus, showing if someone has previously been infected.

另一方面，免疫测定利用免疫系统对病毒的记忆，显示某人以前是否被感染过。