I must complain about…
I am not satisfied with…
I feel something should be done about…
I am writing to inform(告知，代替tell)you that I find…unsatisfactory…
I am writing to express/ air dissatisfaction/ disappointment/ concern regarding …
The noise disturbs my sleep so that I can't concentrate during the work time, and as a result, I have made several mistakes these days.
For me this environment is very difficult to make studies and I need a quiet room.
I expect to hear from you soon.
Please give this matter your immediate attention.
I would be very grateful (感激，代替thanks)if you could look into the matter as soon as possible. And I am looking forward to an early reply.
It is high time you took some measures to solve…
I hope you will take steps to rectify(纠正、改善，代替improve) this situation soon.
I believe you will take my complaints seriously. I would ask you to give back my money, or I would file my complaint(投诉) to the authorities concerned(相关部门).
To solve this problem/ surmount this difficulty/ improve the situation/ crack this hard nut(解决问题), I hope to draw the attention of the authorities concerned.