to study / to learn

basis, foundation / (martial arts) kihon

he / distal demonstrative, something far off removed from both speaker and listener: that / boyfriend

distal demonstrative, something far off removed from both speaker and listener: that, yon / particularly, male personal third person pronoun: he / by extension from he: boyfriend

he; boyfriend

fundamental, basic

(colloquial) current boyfriend

everything

(slang) Alternative form of 彼氏 (kareshi, “boyfriend”)

everyone, one and all