英语作文书信的写作是初中英语学习的重点之一。为了提高作文书信的质量，需要掌握一些万能句子模板。下面是一些初中英语作文书信万能句子模板：

1. 开头段万能句子：

1）I am writing to express my…

2）I am writing to apply for…

3）I am writing to inform you that…

4）I am writing to apologize for…

2. 主体段落万能句子：

1）Firstly, it is widely known that…

2）Another important point is that…

3）Moreover, it is worth noting that…

4）Furthermore, it is essential to mention that…

5）In addition, it should not be forgotten that…

3. 结尾段万能句子：

1）In conclusion, I strongly believe that…

2）To sum up, it is clear that…

3）In summary, I would like to say that…

4）Therefore, I would appreciate it if you could…

5）Thank you for your attention to this matter.

以上是初中英语作文书信常用的万能句子模板。这些模板可以帮助初中生在写作文书信时，更加流畅和有逻辑性。但是，同学们在运用这些模板的时候，也需要注意句子的合理性和语法正确性，才能写出高质量的作文。