Necessary actions that will take place under any conditions
people without a car going to work by public transport
students going to school
goods delivieries
Optional actions that will take place under good conditions
walkers tempted to stop in front of something interesting
choosing walking or biking instead of taking the car
going outside for lunch to enjoy the nice weather
Social the city as a meeting place
people asking for directions
people greeting friends in the street
children playing outside, making new friends