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major earthquake; large earthquake
大地震の後、多くの建物が倒壊した。
After the major earthquake, many buildings collapsed.
大地震に備えて非常食を準備した。
I prepared emergency food in preparation for a major earthquake.
百年に一度の大地震がこの地域を襲う可能性がある。
There is a possibility that a once-in-a-century major earthquake could strike this area.