I’m writing to extend/express/convey my gratitude to you for your generous help.
It is your generous help that enables me to obtain this splendid opportunity.
It was your hospitality and great help that made my journey fruitful and worthwhile.
I really hope you can come to XX for a visit when it is convenient for you.
Thanks again. Please accept my sincere thanks for your caring and efforts, which I will never forget.
I’m writing to apologize to you for my failing to go on a trip to Beijing with you, which I have promised you.
I really hope that you can accept my apologies and understand me. I would appreciate it if you allow me to fix another time to show you around some places of interest in Beijing.
Once again，I’m sorry for any inconvenience I’ve caused. Hope you can accept my sincerest and deepest apologies and forgive me for my fault.
I’m writing to express my dissatisfaction about the mobile phone which I bought last month in your store.
I am one of your customers. I’m writing to complain about one of your waiters’ improper and rude behaviors.
There are some main reasons why I am not content with…First, … What’s worse, … Eventually, …
I sincerely hope that you will look into the matter seriously and proper measures should be taken to prevent such an incident happening again.
I would appreciate it very much if you could take measures to solve the problem as soon as possible.
I am writing to congratulate you on your winning the first prize in the English Speaking Competition.
How happy I am to hear that many years of your efforts have paid off!
3. 我确信正是你的努力使你成功。I know for sure that it is your hard work that leads to your success.
4. 你的成功给了我极大的鼓舞。Your success has greatly encouraged me to study harder.
5. 祝你在学习和工作上有更大的成功。I wish you greater success in your studies and work.
I have some trouble in using proper English words to express my thoughts, so I’m writing to you to seek some help.
2. 不知道你是否能给我一些建议。I wonder if you could give me some advice.
3. 但不幸的是，我发现很难适应新环境。Unfortunately, I find it quite difficult to adapt to a new environment.
Facing these problems, I’m seized with fear and anxiety and I hope that you will be kind enough to help me.
5. 我相信你的任何建议都会帮到我。I’m sure that any advice will be a big help to me.
6. 如你能及时回复，我将感激不尽。Your kind early reply would be greatly appreciated.
I’m writing to know whether it is possible for you to provide me with some information regarding...
Learning that you are having some difficulty in learning English, I’m writing to share with you some advice concerning the problem.
Here are some suggestions for you to change the situation.
3. 我希望我的建议对你有用。I hope you will find these proposals/suggestions/ helpful/useful.
I can’t tell you how sorry I felt when I heard that an accident happened to you and you had your left leg injured.
The truth is that everyone may have one of those terrible experiences.
3. 如果需要帮助，请告诉我。If I can be of any help, please don’t hesitate to let me know.