Re: continent, a country, a state, a nation, a province and a county?
A continent is a natural formation of the planet.
A nation and a country are the same thing.
Many nations are composed of either states of provinces. The United States of America has 50 states, for example. Canada has several provinces.
There is one definition of a state that means "nation" or "country."
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.