I think it is not necessary, just arrive early and leave the seat.
No, you do not need to make reservations to play tennis. Sometimes there are tennis lessons going on, but there are always empty courts available to use - from my experience at least.
Sorry no clue
No, I don't think so It is open to the public and on a first come, first served basis. (Had to use Google Translate. Was stationed in Korea in the Army, but it's been many many years)
I'm sorry I don't know what you are asking?
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