投诉信,帮我看看有语法错误吗?谢谢!投诉信（155）DearSalesManger,IamaseniorintheComputerScienceDepartmentofTsinghuaUniversity.IamafraidthatIhavetomakeacomplaintaboutthebookwhichisentitledPracticalWriti

Question

投诉信,帮我看看有语法错误吗?谢谢!
投诉信（155）
Dear Sales Manger,
I am a senior in the Computer Science Department of Tsinghua University. I am afraid that I have to make a complaint about the book which is entitled Practical Writing and Reading for NETEM.
The reason for my dissatisfaction is that the book is a pirated one. To begin with,much of my valuable time and energy have been wasted in reading the book since it is quite hard to identify many words in the book. What's more,I have not benefited from reading the book since some of keys to the exercises are misprinted.Under these circumstances, I find it very necessary to tell you these problems.
I appreciate it very much if you could change a new one,preferably return all the money back to me.Thank you for your consideration and I will be looking forward to your reply.

Yours sincerely
Li Ming

Answer 1

Dear Sales Manager 应该改成 customer service manager,通常sales manager 只管业务,
不处理售后服务的纠纷,除非你是他们的长期客户.
some of keys to the exercises (keys 应该改成answers)
I'd appreciate it very much if you could EXchange for a new one
Thank you for your consideration 改成 thank you for your prompt attention