What it means
いまだに means “even now” or “still” and indicates that a situation has continued up to the present. It often suggests that the speaker expected the situation to change earlier, so it can convey surprise, concern, dissatisfaction, or emphasis on an unresolved state. It is an adverb placed before the clause or predicate it modifies and is especially common with negative, potential, or result-state expressions, although it can also modify affirmative predicates.
Usage note
いまだに is neutral to formal in register and is not itself a polite form. It often has a stronger sense of unexpected continuation than まだ, so it should not be used as a completely interchangeable substitute in every context.
How to use it
いまだにその問題の原因が分かりません。
Even now, I do not understand the cause of that problem.
いまだにその問題の原因が分からない。
Even now, I do not understand the cause of that problem.
Example sentences
いまだに古い校舎の時計が正確な時刻を示している。
Even now, the clock in the old school building is showing the exact time.
事故から三日もたったのに、いまだに道路の通行止めは解除されていない。
Even though three days have passed since the accident, the road closure has still not been lifted.
改修工事が完了したはずなのに、いまだにエレベーターを利用できない。