被发送（Sent）：电子邮件已发送，但收件人可能未收到。（Email sent from your end but it might not received to recipient.）

被退回（Bounced）：电子邮件未能到达收件人。（The email has failed to reach the recipient.）

被打开（Opened）：电子邮件已被查看并打开。（The email has been seen, and opened.）

被点击（Clicked）：电子邮件中的链接已被单击。（Links in the email have been clicked.）

打开但未回复（Opened and Unreplied）：发送的邮件已被打开但未回复。（Email sent from your end is opened but unreplied.）

未回复（Unreplied）：发送电子邮件，但收件人未回复。（Email Sent from your end but not replied by the recipent.）