They kept a copy of that and they filed it away, so the government had a complete record of your payments into the system.

邮局留下存根并且归档保存，这样政府就能完整的记录下,你的支付情况。

耶鲁公开课 - 金融市场课程节选

Here, I've just picked a couple of the pictures that I showed you last time when we were talking about cell communication in the immune system, What happens after the vaccine is introduced into your body is that it initiates cellular events.

我挑选了,我上次给你们展示的几幅图片,当我们讨论到,免疫系统中的细胞沟通时,讲到过当人体接种疫苗之后,能够触发,细胞活动

耶鲁公开课 - 生物医学工程探索课程节选