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swimming in the ocean; sea bathing; seawater bath; going for a dip in the ocean
毎年夏になると家族で海水浴に行く。
Every summer, we go swimming in the sea as a family.
海水浴場は人がたくさんいて賑わっていた。
The beach was crowded with many people.
海水浴の後はシャワーで砂を洗い流す。
After swimming in the sea, wash off the sand with a shower.