Definition (請求)
A phrase used to politely request something, indicating gratitude if the request is fulfilled.
感謝不尽（禮貌用語）
I would appreciate it if you could inform me in advance whether you will be attending.
如果您能提前告知是否會參加，我將不勝感激。
I would appreciate it if you could submit the report on time.
如果您能準時提交報告，我將不勝感激。
I would appreciate any assistance you can offer.
我將非常感謝您能提供的任何幫助。