I have finished my exam, but the result will come out on 25 June. I don't know how to fill the 20 days~
Well done, fino, you must be glad it's over!
I would say you've earned your right to put your feet up for a bit, and do absolutely nothing at all! The brain definitely needs a rest and a clear-out after exams. Then do whatever brings you the greatest happiness and makes you feel most alive.
Tennis-wise, of course, there's the Aegon and Halle grass tourneys (ATP) at the moment (I don't know if they're broadcast in China) and Wimbledon starts on 21 June.