开头：1、开头点名，可以加个敬语。
如Dear President；Dear teacher等等。
2、点名自己的身份。
如，I am a student of Class Seven, Grade Two of our school.
我是我们学校二年七班的学生。
3、说明写信的目的。
如I am writing to share some advices with you.
我写信是为了提些建议。
中间：中间写你为什么要提建议，以及提什么建议。态度要诚恳。如，
We all know that study is the most important task for senior students, so it’s necessary for us to spend most of our time in study.
我们都知道学习是高年级学生最重要的任务，所以我们有必要把大部分时间花在学习上。
However, proper rest is necessary for us as well. But in our school, we only have a short night to rest, which I think it’s not good to us.
然而，适当的休息对我们也是必要的。但是在我们学校，我们只有一个短暂的夜晚休息，我认为这对我们不好。
I did a survey in our school that collect the ideas about having a longer rest every week. Almost all students say that they need more time to rest and relax.
我在我们学校做了一项调查，收集了每周多休息的想法。几乎所有的学生都说他们需要更多的时间休息和放松。
结尾：表达自己的愿望。
I will be more than happy that you could accept the suggestion.
我很期待你能够接受这个建议。
英语作文:李华写给李刚的学习英语建议信？
Dear teacher,
As your student,I'd like to give you some suggestions on behalf of all my classmates.First,I want to say I love you. And I want to tell you that the smile on your face in English class gives us confidence. Then, we think we will love you more if you make your lessons more lively and more interesting. Also, we think that we are all excellent and hope to be more often praised by you. What’s more, We’d like you to give us some reasonable suggestions instead of orders. Finally, as you are always working very hard, it is quite important for you to learn to have a rest and take care of yourself! Best wishes to you!
Yours, Li Hua