that's what … is about
De eso es de lo que estaba hablando.
That's what I was talking about.
Así que de eso es de lo que hablaremos hoy.
So that's what we'll be talking about today.
— Fack ju Göhte (2013)
Y de eso es de lo que quisiera hablar.
And that's what I'd like to talk about.
That's what it's all about.
That's what I'm talking about.
De eso es de lo que quería hablarte.
That's what I wanted to talk to you about.
De eso es de lo que estoy preocupado.
That's what I'm worried about.
That's what I was talking about.