彼は禁固の身だ。

he; him; his; boyfriend

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

imprisonment; confinement

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

body; oneself; one's place; one's position; main part; meat (as opposed to bone, skin, etc.); wood (as opposed to bark); blade (as opposed to its handle); container (as opposed to its lid)

be; is; indicates past or completed action; indicates light imperative