Formal vs Informal

In business writing it is essential that you do not mix the formal with informal writing styles. Here is a list of some formal expressions and their infomal equivalents.

Thank you - Thanks
I would like to apologize for … - Sorry for …
I would appreciate it if you … - Can you … ?
Would you happen to know …? - Do you know … ?
Unfortunately, I will not be able to … - I can’t …
I am unable to say whether … - I don’t know whether …
I would rather not … - I don’t want to …

May I make a request? - Could I ask you for something / some help?
I appreciate that this will be difficult for you. - I know that this is not going to be easy.
Would you be able to attend a meeting on the 4th of June? - Can you meet up on the 4th of June?
Please contact me at any time. - Feel free to call any time.
I would like to apologize for … - Sorry for …