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very; extremely; surprisingly; fairly; quite; considerably; awfully; terribly
terrible; horrid; contemptible; reprehensible
remarkable; extraordinary
ずいぶん待たせてしまった。
I kept you waiting for quite a while.
今日はずいぶん寒いですね。
It is quite cold today, isn't it?
ずいぶん上手になりましたよ。
You have gotten quite good!