RegEx for email so that it fails if the email does not have at least 1 letter somewhere before the @

I have tried to find a solution to my problem here and here but without luck.
I have written these 2 RegExes for email validation which pretty meet almost all of my criteria
RegEx 1
^\w?[A-Za-z]{1}\w?@[a-z]+.[a-z]{2,}(.[a-z]{2,}){0,1}$
RegEx 2
[\w.-]+@[a-z]+.[a-z]{2,}(.[a-z]{2,}){0,1}$

But they do not solve 1 critical issue.
I want the RegEx to fail when matched with something like:
_@gmail.com
_@gmail.com
8@gmail.com
8@gmail.com
88@gmail.com
8@gmail.com

So basically I want the email to have at least 1 lower or upper case letter and it does not matter it is at the beginning , middle or end of the email itself(before the @).

Could you please help me with this?

>Solution :

Use this.

^\w*[A-Za-z]\w*@[a-z]+.[a-z]{2,}(.[a-z]{2,}){0,1}$