I don't understand this particular line:
The context in which you could use sortir de [ville] to express to leave [city] is very specific in French (note that it doesn't apply to countries,states,regions etc). It would only refer to an action in progress
Does this mean you can't use sortir de [ville] in future/past tense (Je sortirai de Paris), but you CAN use it in other tenses with countries, states, regions, etc?
Or does this mean you cannot use it with countries, states, regions...and you can only use it with cities if it's an action in progress?
