Don't promise, so that no one will suffer.
Don't promise, so that no one will regret.
Don't promise, so that no one will be abandoned.
Don't promise, if you are not even too sure.

Don't promise, if you are only good at talking.
Don't promise, if can't you even do it.
Don't promise, if you're not really interested.
Don't promise, if you don't even know how to fulfill it.

Don't promise, if it will only come into nothing.
Don't promise, if you can't keep it.
Don't promise, if you're not confident.
And lastly, don't even promise if you already knew that between the two of you don't even exist in the beginning.