当您需要就留学选专业的问题发送邮件时，请遵循以下步骤和注意事项：
邮件主题
确保邮件主题清晰明了，例如：
"Inquiry about degree requirements for XX major"
"Registration question for XX major"
"Request for guidance on choosing a major"
邮件内容
在邮件内容中，请包括以下信息：
个人信息
您的姓名
您的年级和专业
课程和学分
您希望在这学期上哪些课程
您是否已经完成了毕业所需的课程和学分
表达目的
明确说明您发邮件的目的，比如询问课程与专业要求的匹配度
如果您需要换专业，说明您的意图和原因
结尾
表达感谢，并询问对方是否有空进一步交流
邮件格式
使用正式而礼貌的语言
检查拼写和语法错误
发送时间最好选择晚上8点至10点之间
邮件地址
使用学校提供的正式邮箱地址，以显示您的正式身份
示例邮件
```
Subject: Inquiry about degree requirements for XX major
Dear [Advisor's Last Name] or [Professor's Last Name],
My name is [Your Last Name] and I am a [Your Grade] majoring in [Your Major]. I am writing to inquire about the degree requirements for my major and to ensure that I am on the right track with my coursework for the upcoming semester.
I am planning to take [List of Courses You Plan to Take] and I would like to know if these courses align with my remaining degree requirements. Could you please advise me on this matter？
Thank you very much for your time and guidance. I look forward to your response.
Best regards,
[Your First Name]
[Your Last Name]
[Your University Email Address]
```
请根据您的具体情况调整邮件内容。希望这些信息对您有所帮助，