済んだことはしかたがない。

to finish; to end; to be completed; to merely result in something less severe than expected; to feel at ease; to feel unease or guilt for troubling someone; to be sorry

thing; matter; incident; occurrence; event; something serious; trouble; crisis; circumstances; situation; state of affairs; work; business; affair; after an inflectable word, creates a noun phrase indicating something the speaker does not feel close to; nominalizing suffix; pretending to ...; playing make-believe ...; alias; aka; nickname; alternative name; also known as

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

way; method; means; resource; course

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

nonexistent; not being (there); unpossessed; unowned; not had; unique; indicates negation, inexperience, unnecessariness or impossibility; not ...; to not be...; to have not ...