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to shut; to close; to fasten; to lock
to block (a street, entrance, etc.)
to shut in (with snow, ice, etc.); to shut off; to cut off; to cover (e.g. in darkness)
to consume (with negative feelings); to fill (e.g. with sadness); to bury (e.g. in grief)
心を閉ざすなよ。
Don't close your heart.
門は固く閉ざされた。
The gate was firmly shut.
彼は心を閉ざしてしまった。
He ended up closing his heart.