They were engaged in conversation.

他们正谈得来劲。

《牛津词典》

I engaged in conversation.

我刚才忙着谈话呢。

youdao

Engaged in conversation, they did not see me.

他们谈得正来劲，没看见我。

youdao

"A science caf, it's a concept that actually started in Europe, and it was an idea to get scientists engaged in an informal conversation with the general public."

VOA: standard.2010.05.04

The Mets and Team USA were engaged in conversation until about 20 minutes before the game regarding the appropriate course of action.

WSJ: Wright's Injury Puts Mets In 'World' of Pain

For example, one needed to be at the cocktail parties engaged in conversation to truly understand the magnitude of the real estate bubble.

FORBES: The Poindexter Theory of Economist Failure

The photos showed Kim engaged in conversation and active.

CNN: North Korean leader Kim Jong-Il pictured in public