英语作文建议信的开头、中间和结尾的写作方法如下：

开头

问候和自我介绍：首先，使用正式的问候语，如“Dear [收信人姓名]”，并简短介绍自己。

写信背景信息：简要说明写信的目的，例如，“I am writing to offer some suggestions regarding [specific topic or issue].”

表达关心：可以表达你对收信人困境的关注和愿意提供帮助的意愿，例如，“I have learned that you have some trouble in learning English and would like to give/offer you the following suggestions.”

中间

列出建议：清晰、有条理地列出你的建议。每个建议可以单独成段，确保逻辑清晰。

支持理由：为每个建议提供支持性的理由或解释，使建议更具说服力。

使用连接词：使用连接词如“First and foremost,” “What’s more,” “Last but not least,” 等来组织内容。

结尾

总结建议：简要总结你提出的建议，强调其重要性。

表达希望采纳的愿望：表达希望对方能够考虑并采纳你的建议，例如，“I hope that my suggestions will be helpful for you.”

礼貌告别：使用正式的结束语，如“Yours sincerely, [你的姓名]”，并签上自己的姓名。

```

Dear [收信人姓名],

I hope this letter finds you well. I am writing to offer some suggestions regarding your English learning difficulties.

First and foremost, I believe you should consider enrolling in an English language course to improve your proficiency. This will provide you with structured learning and professional guidance.

What’s more, I suggest you practice speaking English regularly with native speakers or fellow learners. This will help you become more fluent and confident in your communication skills.

Last but not least, it is important to immerse yourself in English media, such as watching movies, listening to podcasts, and reading books. This will expose you to real-life language usage and enhance your understanding of the language.

I hope that my suggestions will be helpful for you. And I am looking forward to hearing from you.

Yours sincerely,

[你的姓名]

```

通过以上步骤，你可以撰写出结构清晰、内容有说服力的英语建议信。