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to serve; to work for; to attend
彼は長年にわたり王に忠実に事えてきた。
He faithfully served the king for many years.
二人の主君に事えることは武士の恥とされた。
Serving two masters was considered a disgrace for a samurai.
神に事える者として厳しい修行を重ねた。
As one who serves the gods, he underwent rigorous training.