Usages of fēng
她 一共 发 了 三 封 邮件 给 我。Tā yígòng fā le sān fēng yóujiàn gěi wǒ.
She sent me three emails in total.
我 刚才 给 她 回 了 一 封 邮件。wǒ gāngcái gěi tā huí le yì fēng yóujiàn.
I just replied to her email.
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