上了班都可以辭, 還沒到那家上班,為甚不可以反悔?
Congratulations!
You always chose what is the best for you and your family.
Wait until you get better offer IN HAND, then deny the other offer.
It is very easy:
Johnny,
I am sending this email to inform you that I will not start working for your company on Aug. 01 2009.
Thanks!