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now (when it is already much too late); at this stage
afresh; anew; again
今更後悔しても仕方がないので前を向こう。
There's no point in regretting at this late stage, so let's look forward.
今更そんなことを言われても対応できないよ。
Even if you say that now, I can't respond to it.
今更ながら自分の過ちに気づいて恥ずかしくなった。
I became embarrassed realizing my mistake at this late stage.