how to write a formal and simple feedback to reply?
when i got a mail from someboby, what should i give a feedback to him or her? usually i write "i've received your email. and thanks for your kindly reply. i'll check it and give you a feedback asap." how about this?

Question

how to write a formal and simple feedback to reply?
when i got a mail from someboby, what should i give a feedback to him or her?  usually i write "i've received your email.  and thanks for your kindly reply. i'll check it and give you a feedback asap."   how about this?

Answer

It would be better to write.
I have received your email. 
Thank you kindly for replying/ thank you for your reply/ thank you for replying. ( I don't think you mean a 'kind reply' ( 'kind' as an adjective here would mean warm / showing understanding or sympathy)
I'll check it and let you know/ give you feedback/ answer you asap.

Answer

Thank you for your email. Please expect a response from me as soon as possible.

Answer

If I were writing it myself, I'd say:

I received your email I will look into it and get back to you shortly.

There are many right ways to say this differently, but this is my usual choice of words... :)