参加自由
さんかじゆう
sankajiyuu
JMdict entry #2838893
- nouns which may take the genitive case particle 'no'noun (common) (futsuumeishi) free-for-all; open-to-all
- nouns which may take the genitive case particle 'no'noun (common) (futsuumeishi) optional (to participate in); non-compulsory