Can "If I would" ever be correct?

conditionals grammaticality would

"I'm not sure if I would ever know this question" is not grammatically correct, but "if I would" is perfectly valid.

Would is a modal auxiliary verb that indicates the likelihood of something; in this case, whether or not the speaker "knows the question." I'm assuming he is referring to the answer to the question; "I'm not sure if I would ever know the answer to this question" is grammatically correct and suggests that the question may be impossible to answer.

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