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to call out to; to hail; to address
to appeal (e.g. to the public); to urge; to exhort; to advise
道で知らない人に呼び掛けられた。
A stranger called out to me on the street.
政府は国民に節電を呼び掛けるキャンペーンをしている。
They are calling on citizens to save electricity.
何度も名前を呼び掛けたが返事がなかった。
I called out their name but got no response.