A short letter

Dear Sir / Madam,

As a regular library user, I feel deep gratitude to you for rendering me convenient service.

As a regular user of your library, I thank you for providing such an excellent service (I am in your debt).

I am writing this letter in the purpose of offering some conducive recommendations to upgrade the quality of your service.

Though it is with a heavy heart that I am writing this letter as I feel there are a few changes (iron out the kinks, if you like) you could make, that would enhance the customer service experience for all.

Firstly, a great many students raise such an issue, which is that it is a waste of time in that the lines waiting for assistances are always long.

While the service desk is excellent, the queues are far too long (many of my peers are of the same opinion). Perhaps another automated return point or an on line system allowing you to extend renewal dates.

Secondly, there are always some students discoursing regardless of others’ feelings so that it has a negative impact on the atmosphere of the library.

Consequently, it is better for you to take some measures or publicize the character of politeness to people to reverse this disturbing trend.

Also the incessant chattering of a few (one rotten apple, ruins the barrel) students who seem to have little regard for other library users, this has an adverse effect on the ambiance of the library.  May I suggest an electronic notice board (with users limited to N numbers of post per day) whereby other users could request a certain person or group refrain from talking.

I wish you will find my proposals useful to you. Your prompt attention to my suggestions would be highly appreciated.

I would be extremely grateful if you could consider some of my proposals, should you require my assistance with any of the above, please call.

Yours sincerely, (Yours faithfully [with a name you can be sincere, otherwise you have to be faithful])
Li Ming

A short letter

Very well written!