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QUESTION:
I know the difference:
(A) REGRET + doing: feeling sorry about what I did in the past.
(B) REGRET + to do: feeling sorry about what I will do now.
However, I don’t exactly understand
what difference exists in the below two sentences:
(A) I regret not working harder.
(B) I regret not having worked harder.
ANSWER
B is strictly more correct
if you are referring to the past.
I regret not having worked harder, because now I am poor, and my children did not receive an education.
You must use A for the present
(and you can use it for the past):
I regret not working harder, because I can hardly afford my daily beer and cigarettes any more. (Present habitual)
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(BUT) Many people, Americans especially, would use A in place of B...
source: usingenglish.com/forum
