ずい分ぶん
Meanings
Adverb
Usually written in kana
1. very; extremely; surprisingly; fairly; quite; considerably; awfully; terribly
But, I guess they must have been pushing themselves pretty hard.
Adjective (な)
Usually written in kana
2. terrible; horrid; contemptible; reprehensible
What a rude greeting.
3. remarkable; extraordinary
Kanji used
part
Pitch accent
ず
いぶん
Composed of
part; portion; amount; worth (as in "two days' worth"); one's means; one's place; one's duty
Examples (1 in total)
We have to put up with a lot of noise when the children are at home.