yoku よく

In Japanese, yoku よ, also spelled yoku 良く, means literally that you've done "good" or have done "well," but it can also mean something happens "often" or "a lot," and it can also mean something is "impressive" to have done, often given unfavorable circumstances, or, also, because of the nerve you had to have to dare do it.

The word yoku よく is the adverbial form of ii いい, or rather, of yoi 良い. Note that yokunai よくない means "not good" instead, because to inflect the negative form of i-adjectives you add the auxiliary nai ない to the adverbial form. And yokute よくて is the te-form of the i-adjective.

Manga: Made in Abyss (chapter 14)

• "To Do Well"
  • よくやった
  • よく頑張った
  • よく出来た
  • よく聞け
  • よく見ると
• よくそんな
  • "Hard to Believe You Did That"
  • "Ugh! I Would Never Do That!!! Don't You Have No Shame?!"
  • "You Peasant, Don't You Know Your Place?!"
• "Often"
  • "A lot"
• Expressions
• Grammar
• 良く, 善く, 能く, 好く, 克く

"To Do Well"

Although yoku よく comes from the adjective ii いい which means literally "good," there's a number of cases where it's better translated as "well" instead of "good."

I mean, you could say "good" instead of "well" in English, but it'd sound goofy.

• You write well.
• You write good.

Some examples:

• yoku mieru よく見える
  [I] can see [that] well.
• yoku mienai よく見えない
  [I] can't see well. (it's dark here, someone switch on the light.)

• yoku wakaru よく分かる
  To understand well.
  I really get that.
  I sympathize with that completely. Hashtag relatable.
• yoku wakaranai よく分からない
  To not understand well.
  I don't really get it.

• yoku shiraberu よく調べる
  To investigate well.

Manga: Gintama 銀魂 (chapter 5)

• Context: something explodes.
• ...nanka
  yoku wakan'nee kedo
  suru beki koto wa
  yoku wakaru yo
  ･･･なんかよくわかんねーけど
  するべきことはよくわかるよ
  I don't really get it, but I really get what I'm supposed to do. (run!!!)
  • wakan'nee わかんねー
    Relaxed pronunciation of warakanai.

"Well Done"

Usually, the adverb yoku よく means "well done" when it modifies a verb in the past tense. For example:

• yoku yatta よくやった
  [You] did good.
  [You] did well.
  Well done!
  • yaru やる
    To do. (in the sense of to have done something tangible, a task, a plan, a mistake, etc. unlike suru する which is "to do" mostly for grammatical purposes.)
• yoku itta よく言った
  Said good. Said well.
  Well said!
  • iu 言う
    To say.

"Thank You For Everything"

It's kind of odd to explain, but a lot of times yoku means "you have done well by doing this" rather than "you have done this well."

To elaborate, let's see an example:

• yoku toreta shashin よく撮れた写真
  A photo [that was] taken good. Taken well.
  A well-taken photo. A good photo.
  • toru 撮る
    To take [a photo].

In the phrase above, we are clearly qualifying the action of "taking" the photo. The photographic technique was "good," in other words, it was "well" taken, that's why it was a good photo.

However, sometimes both "well" in English and yoku in Japanese have little to do with the amount of skill employed in doing something and more to do with the fact that merely doing the thing was a "good" thing to do.

Manga: Gintama 銀魂 (chapter 45)

• Context: characters arrive somewhere.
• umu うむ
  Hmm.
• yoku kita よく来た
  [You] came well.
  • You've done well by coming.
  • Thank you for coming.
  • Coming here was a good idea. (if you didn't come that would've been bad.)
  • kita 来た
    Past form of the irregular verb:
  • kuru 来る
    To come.

That's why, at such times, yoku becomes more like an expression of approval or a compliment rather than a qualifier for the action itself. For example:

• yoku tatakatta よく戦った
  [You] fought well.
  • Not because your mecha shooting skills were pure awesome, but because you saved a lot of lives from inside that Gundam.
• yoku ganbatta よく頑張った
  [You] put effort well. (literally.)
  Thank you. You've worked hard enough. Without you, we wouldn't be able to do this. Your sacrifice won't be in vain. Et cetera.
  • ganbaru 頑張る
    To put effort. To work hard.
• yoku taeta よく耐えた
  [You] resisted well.
• yoku gaman shita よく我慢した
  [You] endured well.

"Well Made"

In the case of the verb dekiru 出来る, because it has two different meanings, we can observe it being used in two different ways.

First, dekiru can mean "able to." In the past, dekita, it would mean you were "able to" do something. For example:

• yoku dekita よくできた
  "Able'd good." (or whatever.)
  You did well accomplishing that.
  You did well having managed to do that.
  You did well having succeeded in doing that.

Second, dekiru can mean "made." This is a less common use of dekiru, but it's still pretty common.

Manga: Rozen Maiden (chapter 3)

• Context: a girl sees a doll.
• yoku dekiteru no nee
  よく出来てるのねぇ
  [She's very] well made, [isn't she]?
• marude honmono no onna-no-ko-chan you
  まるで本物の女の子ちゃんよぅ
  It's like [she's] a real girl!
  • chan ちゃん
    Just a cute suffix added here for extra cuteness.
  • you よぅ
    This is yo よ, the sentence ending particle, but she pronounces it differently.

Note that dekiru doesn't always mean literally "made" in the craft sense. The "made" part can mean something less literal.

• yoku dekita otouto よく出来た弟
  An younger brother [that was] made well.
  [Your] younger brother [was raised] well.
  • Here, "made" means raised. A younger brother that was raised well, educated well, etc. This kind of phrase is usually used as a compliment, like saying "he's a good kid.".

"Don't Slack Off!"

The word yoku is can be used in the imperative to order someone to do something well, to not slack off doing it.

• yoku hatarake よく働け
  Work well.
  • hataraku 働く
    To work.
• yoku kike, kono yarou
  よく聞け　この野郎
  Listen well, [you bastard].
  • kiku 聞く
    To listen.

Manga: One Piece (chapter 43)

• Context: the customer isn't always right.
• umi de kokku ni sakarau koto wa
  海でコックに逆らうことは
  In the sea, defying the cook [is]...
• jisatsu ni hitoshii koui
  自殺に等しい行為
  An act equal to suicide
• datte koto wo
  yoku oboetoke...
  だってことをよく覚えとけ･･･
  Remember [that] well.
  • oboetoke 覚えとけ
    oboete-oku 覚えておく
  • oboeru 覚える
    To remember (something that you learn.)
  • For later. In preparation. (in this case, you remember so next that time you don't make the same mistake.)

Upon Further Inspection

When the adverb yoku is combined with a conclusion, it means "if done well, then..."

In some cases, this translates to: "I did it badly before, but if I do it right this time, then the result is different." For example:

• yoku miru to,
  nanika ga okashii
  よく見ると何かがおかしい
  If [I] see well, something is odd.
  Looking at it [closer], something is odd.
  Upon [further inspection], something is odd.
  • In other words: at first glance there was nothing odd, but looking at it "better" then you can see something is indeed odd.
• yoku mireba niteru よく見れば似てる
  If [I] see well, it resembles.
  Looking closely, [he looks like him.]
  • I.e., at first glance, you didn't notice, but after giving it a proper look, you notice one person resembles another person, etc.
• yoku mirya niteru よく見りゃ似てる
  (same as above.)
• yoku kangaeru to okashii
  よく考えるとおかしい
  If [I] think well, it's odd.
  [If you stop to think about it], it's odd.
  [On a second thought], it's odd.

Manga: Doraemon ドラえもん (chapter 10)

• Context: Doraemon compliments Nobita.
• jii
  ジー
  *stare* (mimetic word.)
• yoku miru to, kimi wa jitsu ni rippa-na ii kao wo shiteru ne.
  よく見ると、きみはじつにりっぱないい顔をしてるね。
  Looking [closer I] see [that] you [have] a really handsome good face.
  • The word shiteru comes from suru which means "to do," but in this case it means "to have." That's because suru can also mean "to be in a way." When it's used toward clothes, it means "to wear" because you be in a way that includes the clothing. Since you don't wear a face, it means "to have" here, because you're in a way that includes a handsome face..
• honto kai.
  ほんとかい。
  Really?
  • honto ほんと
    Really. (and kai is the same as ka: a question particle.)

"Impressive"

The adverb yoku よく can also be used as an expression of disbelief: for something that's so good you don't believe, or even something that's so bad you can't believe.

The reason this happens is because yoku can mean "it's impressive that..." Sometimes you're impressed by something good, but sometimes you're impressed by how bad something is.

"Hard to Believe You Did That"

Sometimes, yoku よく means it's "impressive," "incredible," "hard to believe," that you actually managed such a feat as the one you did, because of how hard it is.

• yoku sonna koto shitteru
  よくそんなこと知ってる
  Done well knowing something like that.
  Impressive you know something like that.
  Incredible you know something like that.
  Hard to believe you know something like that. (because that's impressive.)

This is an extension of the "did well" meaning: you did so amazingly well it's actually hard to believe. Basically, it's a mix of compliment and disbelief. For example:

• yoku sonna soubi de kuria dekita
  よくそんな装備でクリアできた
  Did well being able to clear [the game] with that equipment.
  Hard to believe you could beat the game with that equipment.
  Impressive you managed to beat the game with that equipment.
  I honestly wouldn't have been able to beat the game with that equipment the way you did.
  (and so on.)

Note that, in the phrase above:

• sonna soubi de そんな装備で
  With that kind of equipment.

Narrows down how the action "beating the game" was done. In other words, beating the game isn't that impressive, but beating the game with that sort of equipment is impressive.

Most of the time yoku is used like this, it has an adverb which narrows down how the action was done and why it's so impressive.

And often, it's used with the demonstrative pronouns konna, sonna, anna, because they mean "with something like this," implying, "impressive you did it using something so bad like this."

"Ugh! I Would Never Do That!!! Don't You Have No Shame?!"

Sometimes, yoku よく can express disbelief for the lack of shame or common sense that someone displays. This usually happens when someone does or says something totally out of place, or that the speaker would never have the nerve to do, for whatever reason.

• yoku sonna ni taberu ne
  よくそんなに食べるね
  Impressive [that you] eat that much.
  • The speaker is impressed because the speaker wouldn't eat so much.
  • That's because:
  • First, he looks like a glutton to the people around him.
  • Second, he will get fat.

Note that, in this case, the speaker may be disgusted by the actions of the person, or just in disbelief of their faux pass. Also note that there's no way to discern between this use, which criticizes the person, and the use where the speaker is complimenting the person.

• yoku sonna ni taberu ne!
  よくそんなに食べるね！
  Amazing [you] eat so much!
  • In this a compliment?

You can only tell one apart from the other from context, or, more directly, from the facial expression of the speaker. If they're making a face of disapproval, it's a critique, of approval, it's a compliment.

Manga: Historie, Hisutorie ヒストリエ (chapter 4)

• Context: someone is speaking blatant falsehoods for everyone to hear. One of the people listening then thinks:
• yoku iu yo naa......
  よく言うよなァ･･････
  Amazing [he] says......
  • Amazing he's saying stuff like that......
  • Amazing he can say stuff like that with a straight face......
• We can tell the character in the panel is criticizing because his face is literally frowning upon the guy he's talking about.

Of course, this "impressive" usage isn't exclusive of Japanese, it works in English too: "it's impressive you can do that, given that you... (insert a number of reasons you shouldn't be the one doing that here)" And the sort.

In a number of times, yoku is accompanied by a verb in the potential form, that means "able to," including dekiru. This happens because the critique isn't just toward the fact they did something, but that they were "able to" do something unthinkable in first place.

• yoku sonna koto ieru ne
  よくそんなこと言えるね
  Impressive [that you] can say something like that. (given that you're really not the person to say something like that in a situation like this.)
• yoku sonna koto dekiru ne
  よくそんなことできるね
  Impressive [that you] are able to do something like that. (in a situation like this, etc.)

Of course, it's not always in the potential, can be in the past too:

• yoku sonna kakkou de soto ni deta
  よくそんな格好で外に出た
  "Did well leaving outside with that appearance."
  Impressive you went outside looking like that.
  I can't believe you went outside looking like that.
  I would never leave outside looking that way.
  • deru 出る
    To go out. To leave.
  • kakkou 格好
    Appearance. How someone looks. What they're wearing. Etc.

"You Peasant, Don't You Know Your Place?!"

Sometimes, yoku よく is used by pretentious characters to smugly make fun of someone they look down at. That is, to tell them they should know their place and blame them for having the nerve to dare try do something unfitting of their inferiority.

Of course, this mostly happens in anime, not in real life.

And again, there's no grammatical different between this and there rest. The nuance comes from the context. If you have a bully character bullying someone saying yoku, it's probably like this:

• yoku sonna koto ieru ne
  よくそんなこと言えるね
  Amazing [that you] can say something like that. (you peasant.)
  How dare you say something like that! (given that you're a peasant.)

A stronger version of this is yoku mo よくも, which basically always means "HOW DARE YOU?!?!?!" and it's used by enraged characters. (not just by bullies, good guys use it too.)

"Often"

The adverb yoku よく can also mean "often" in Japanese. This probably comes from the fact some things you do "well" you do "often," but honestly, it's pretty much an entirely separate meaning.

• yoku aru koto
  よくあること
  Something [that] exists often.
  Something [that happens] often.
• yoku koko ni kimasuka?
  よくここに来ますか
  Do [you] come here often?

In fact, there are times you have yoku meaning "often" for something that's not "good" at all.

Manga: Mob Psycho 100, Mobu Saiko Hyaku モブサイコ１００ (chapter 53)

• Context: woman surrounded by evil spirits explains her situation.
• mukashi kara
  "hiki tsuke taishitsu" de...
  昔から【引き付け体質】で･･･
  Since a long time ago [I've] been of "attracting disposition."
  • I've always been the sort of type that attracts things.
  • mukashi kara 昔から
    Since the past. Since a long time ago. Since always.
  • taishitsu 体質
    Physical quality. Disposition. Nature. (you know how some people have a body that has some weird quality like sweating a lot when they're nervous or phasing through walls? It's like that.)
• yoku rei ya fishigi na mono wo
  chikaku ni yonde shimau-n-desu
  よく霊や不思議なものを
  近くに読んでしまうんです。
  Often [I] end up calling near [me] spirits and strange things.

"A lot"

Note that you can also translate yoku as "a lot," but this is obviously in terms of frequency—how often something happens—and not quantity—how much of something there is:

• yoku toraburu ni makikomu
  よくトラブルに巻き込む
  To get involved in trouble a lot.
  (and not "to get involved in a lot of trouble.")

Note the difference between yoku and takusan, for example:

• sou omou hito wa yoku iruそう思う人はよくいる
  People [who] think like that exist a lot.
  You can often find people who think like that.
  You frequently find people who think that way.
• sou omou hito wa takusan iruそう思う人はたくさんいる
  People [who] think like that exist a lot.
  There are a lot of people who think like that.
  People that think that way are many.

Manga: Made in Abyss (chapter 14)

• Context: Ozen gets told a thing.
• sore
  yoku iwareta yo
  それ　よく言われたよ
  [I] have been told that a lot.
  • People tell me that a lot.
  • I get told that a lot.
  • I get that a lot.

Expressions

The word yoku よく is the adverbial form of ii いい even when it's part of an expression, set phrase or compound. For example:

• naka ga ii 仲がいい
  "Relationship is good."
  They're friends.
• naka yoku naru 仲良くなる
  To become so the relationship is good.
  To become friends.
• naka yoku suru 仲良くする
  To make it so the relationship is good.
  To make peace.
  To become friends. (deliberately.)

• kakko-ii カッコいい
  "Good-looking."
  Cool.
• kakko-yoku tatakau
  カッコよく戦う
  "To fight looking good."
  To fight [in a way that's] cool.

• kimochi-ii 気持ちいい
  "Good-feeling."
  Pleasant.
• kimochi-yoku nemuru
  気持ちよく眠る
  "To sleep feeling good."
  To sleep pleasantly.

Grammar

Translated, both yoku よく and ii いい mean literally "good." The difference is that ii is an adjective, it comes before nouns, while yoku is an adverb, it comes before verbs. For example:

• tenki 天気
  Weather. (a noun.)
• ii tenki いい天気
  Good weather.
  • Adjective + noun.
• *yoku tenki よく天気
  (ungrammatical, unless there's a verb after tenki.)
  • Adverb + noun = wrong.
  • yoku tenki wo ki ni suru
    よく天気を気にする
    To mind the weather a lot.
  • Adverb + noun + verb = alright.
  • ki ni suru 気にする
    To mind. To care. To pay attention to.
• iu 言う
  To say. (a verb.)
• yoku itta よく言った
  Said good. Said well. Well said.
  • Adverb + verb.
• *ii itta いい言った
  (ungrammatical.)
  • Adjective + verb = wrong.

Beware of quoting particles like to と, tte って and ttsu っつ. A quote is often a literal and isolated sentence. So an ii in a quote won't change to yoku just because the phrase outside the quote ends in a verb. For example:

• omou 思う
  To think.
• yoku omou よく思う
  To think [about something] a lot.
• ii to omou いいと思う
  "Good," [I] think.
  I think it's "good."
  • Here, the adjective ii いい, "good," is isolated inside a quote before the quoting particle to と and therefore doesn't change into yoku よく.

良く, 善く, 能く, 好く, 克く

One surprising thing about yoku よく is that this same word can be written with five different kanji: 良く, 善く, 能く, 好く, and 克く.

This may sound a little problematic for you, after all, which kanji should you write the word with?

Now, if you were paying attention to the examples posted in this article, you should have noticed that yoku よく is pretty much always written without kanji. So you don't really need to decide which kanji, because you won't write it with kanji in first place.

But if you really, really need to, you write it as yoku 良く. The spelling yoku 善く is much less common, but it's still used. However, the rest pretty much isn't used in modern Japanese, apart from some set phrases, idioms, proverbs, etc.

Of course, there are actual differences between each spelling. See:

• 良く
  Literally "good," the opposite of "bad."
  • yoku miru 良く見る
    To sell well. (instead of badly.)
• 善く
  Also "good," but the opposite of "evil."
  • yoku ikiru 善く生きる
    To live well. (i.e. do not sin.)
• 能く
  Emphasizes the capability of something.
  • yoku aru 能くある
    To exist often. To happen often.
    i.e. it's very capable of existing, happening.
• 好く
  It's "good" in the sense it's "preferable," konomashii 好ましい.
  • yoku utau 好く歌う
    To sing nicely.
• 克く
  This one is only used in the sense of enduring a hardship.
  • yoku tatakatta 克く戦った
    Fought well.

Another example:

• yoku suru 善くする
  To improve it. To make good.
  • shakai wo yoku suru 社会を善くする
    To improve society. (to make society well.)
• yoku suru 能くする
  To be able to do it.
  • sho wo yoku suru 書を能くする
    To be able to do calligraphy. (i.e. to write well.)
    

References:

• 良く分かりました？ - detail.chiebukuro.yahoo.co.jp, accessed 2019-02-10.
  The answer explains 能く, 好く, 克く
• 『良い』と『善い』の違いは?? - detail.chiebukuro.yahoo.co.jp, accessed 2019-02-10.
  The answer explains 良く, 善く.