Here’s a little lesson from the notes I took during my first year of Japanese class. I took these notes on June 29, 2001, which must’ve been a Friday – my fifth day of Japanese and I’d already learned me hiraganas!

These are all adverbials that you can pair with verbs to express the degree to which you do that verb.

全部（ぜんぶ）食べた                                             [Subject] ate all [of object]
ほとんど食べた                                                          [Subject] ate most [of object]
よく食べた                                                                   [Subject] ate quite a bit [of object]
まあまあ食べた                                                          [Subject] ate a good bit [of object]

あまり食べなかった・よく食べなかった           [Subject] didn’t eat much [of object]
ほとんど食べなかった                                             [Subject] hardly ate [object]
全然（ぜんぜん）食べなかった                            [Subject] didn’t eat any [of object]