I have a city that is multi-national. Womeone wrote that if you want to build a worker or a settler, you could choose your population unit or units that will be forfeited to build the worker or settler. In my case I want it to be a foreign national population unit. I do not know how to choose it. Does anyone know how? I have tried to take the population unit off of a production square but it did not pick it it picked a population that was of my nationality.