邮件发送必须靠服务器?新手必看的运作真相,邮件发送的奥秘,揭秘新手必知的邮件服务器运作真相
Does email sending have to rely on a server? The operational truth that beginners must read, the mystery of email sending, revealing the operational truth of email servers that beginners must know
以上为机器翻译结果，长、整句建议使用 人工翻译 。