vacant lots, lawns, bicycles, sidewalks, Han River banks, roadside trees, Han River, sky
The open and grass fields are very static, and bicycles and pedestrians are all walking or running at different speeds.
The Han River flows steadily behind the Han River flows steadily. Airplanes are often seen in the sky (but not in the picture), which is so far that they eventually fly at a speed similar to that of a person or bicycle.
It's a spot where different speeds can be seen at once!
Bicycles only run in a row, and people walk in a row on the same time.
Bicycles are fast but efficient, so they run in a line, and even if they run together, they seem to go alone.
People are inefficient but slow and walk together. It looks like we're going together when we're next to each other.
Flights. Omit.
Observation that inefficiency seems human.