1 and 2 both make sense and mean the same thing. However, I find 2 to be awkward. 3 doesn't make sense to me.
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CalifJim2: Making a promise also entails the risk of being not able to fulfill it. No.It's not that I don't believe you but I would like to know what rule of syntax made you to rule out the second as an incorrect variant?
CalifJimMore realistic:
-- OK. I promise. [muttering to himself an