adverb, adverb taking the 'to' particle
very; extremely; quite; considerably
Adverb expressing a high degree, often with a nuance of surprise or unexpectedness. Used with adjectives, verbs, and nouns.
ずいぶん大きくなったね。
You've grown so much!
ずいぶん待ったけど、彼は来なかった。
I waited quite a while, but he didn't come.
terrible; horrid; contemptible
Adjectival use expressing strong negative judgment about a person or situation. Often used with だ/な.
そんなことを言うなんて、ずいぶんだね。
That's a terrible thing to say.
Adjectival use expressing strong positive or neutral surprise at something outstanding. Less common than the adverbial sense.
彼の才能はずいぶんなものだ。
His talent is truly remarkable.
It's really cold today, isn't it?
He's really changed a lot, hasn't he?
That's a pretty terrible thing to say.
Quite a lot of time has passed since then.
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