testify before Congress about what he knew and was doing about covid.

在国会就他所知及所采取的应对措施作证。

What did he do 111 times yesterday in front of Congress regarding what he did and what he knew about covid?

昨天他在国会就新冠一事，针对他的所作所为和他所知的情况，重复说了111次什么？

I plead the fifth.

我行使第五修正案权利，拒绝回答。