subject line

US /ˈsʌbdʒekt laɪn/
UK /ˈsʌbdʒekt laɪn/
"subject line" picture
1.

主题行, 邮件主题

the line of text that appears in an email, indicating the topic of the message

:
Please make sure to include a clear subject line in your email.
请务必在您的电子邮件中包含清晰的主题行
A good subject line can increase the open rate of your emails.
一个好的主题行可以提高您电子邮件的打开率。