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to finish; to stop; to end; to put an end to; to bring to a close
to close (a business, etc.); to close down; to shut down; to shut up
to put away; to put back; to keep; to store
to do completely; to finish
to do accidentally; to do without meaning to; to happen to do; to end up ...
宿題を全部やってしまった。
I finished all my homework.
大事な手紙を捨ててしまったかもしれない。
I might have thrown away an important letter.
つい余計なことを言ってしまって後悔している。
I regret having accidentally said something unnecessary.