這裡要為你介紹英文email的兩種基本類型，即商業和個人電子郵件。您既可用來發送第一封email，也可以用來回覆之前寄出的郵件。讓我們以一封與工作有關的英文email為範例，來說明如何回信。
Vance早些時候寫給Evan一封email，其主旨(Subject)為：June 6 follow-up meeting。Vance要求Evan確認下週一的會議，以下是email內容：
Hello Evan,
Thank you again for coming in to meet with me today. As agreed, I have scheduled a follow-up meeting with our director, Roger and Carrie, for next Monday, June 6 at 2PM. Would you please confirm that you are available at this time?
I look forward to seeing you again. Have a great week!
Regards,
Vance
Evan收到email後，使用Re: June 6 follow-up meeting做為回覆的主旨標題，回信如下：
Hello Vance,
Next Monday at 2 PM works just fine for me. Thank you for setting up the meeting. I look forward to seeing you all on the 6th.
Best,
Evan
這裡要告訴你的是，我們在回信時，請記住保持相同的主旨標題(subject)，例如以上的Re: June 6 follow-up meeting。這是對某一個email主旨的一系列回覆。雖然您可以修改標題或添加字句，但是完全更改主旨標題可能會造成混淆。這條主旨的訊息簡短而重要，通信雙方很容易了解其中最重要的訊息。我們從以上email的內容可看出Evan寫得很得體又有禮貌。他用了一個合適的 “Thank You” ，並且包括了一句客套的結尾句。這封email就可發送出去了。
以某種方式回覆email比重頭開始寫一封電子郵件更容易。寄件方已經開啟了email主旨， 因此，如果您要回信，則大多數情況下您可以使用發件人使用的相同主旨標題。 如果他們使用正式的用語，你就使用正式的用語。
英文email回信使用的句子
以下是您可以在回覆英文email時使用的一些有用的句子：
Thank you for writing.
Thank you for your interest.
Thank you for contacting me.
Thank you for reaching out to me. (less formal)
Thank you for the update.
See my responses below.
See my responses below in bold.
See my responses below in blue.
Thank you for your email. I’ll respond in detail in tomorrow.
Got your message. Thank. I’ll get back to you by tomorrow. (informal)
I apologyize for the delayed response. (formal)
Sorry for the late reply.
Sorry for the late response.
Sorry for not getting back to you right away.
回覆個人email
我們再來看看另一個英文email模型。這個格式稍微不那麼正式。這是給Evan的另一個電子郵件，它的主旨標題是: Reference。
Subject: Reference
Hi Evan,
Just wanted to let you know I was contacted by Vance from XYZ company today. He was very friendly, and it was easy to recommend you for the job.
Good luck!
Best,
Cory
你能預測Evan會如何回覆嗎？ 我們來看看回信內容：
Subject: Re: Reference
Hi Cory,
Thanks for letting me know. I really appreciate the positive reference. I’ll let you know how it goes.
Take care,
Evan
你可看出Evan寫的email有什麼優點嗎？ 我們從以上的回信，可以看到Evan在回覆信中使用了Re: Reference相同的主旨標題，並且保持著同樣的友好語氣，這封email很簡短，但是目的明確。