a jak można używać czegoś co nie istnieje

Od czasu do czasu

Nah, you can take it.

She sounds like "mozgu," not "mózgu," unless Polish "Ó" sounds different than Polish "U." It doesn't sound like "muzgu" to me.

Not if he is a politician.

How would "Use your brain" be translated? "Uważaj mózg"?

Eating brains