Both の and こと turn verbs into nouns, but they feel different:
————————

こと is more conceptual and abstract. It treats the action as a general idea and sounds more detached. It's often used for information, ideas, or facts.

の feels more direct and personal. It points to the actual action as it happens. It sounds more immediate, and it's commonly used for things you directly see, hear, feel, or control.
————————

→ 私は死ぬことが怖い = "I'm afraid of death"
Here, the action is treated as a general concept.

→ 私は死ぬのが怖い = "I'm afraid of dying"
This feels more immediate and personal, as if you're afraid of dying rather than death as an abstract idea.
————————

The difference becomes clearer with direct perception. When you directly witness something, you usually use の.

→ 私は子どもが泣いているのを見た = "I saw a child crying"
What you saw wasn't the concept of a child crying—you saw the action itself.

The same contrast appears with hearing, especially when comparing direct perception and reported information.

→ 火山が噴火したことを聞いた = What you heard was the news of the volcano erupting.
Here, you received information about the event.

→ 火山が噴火したのを聞いた = You were there when the volcano erupted. You directly heard it.
In this case, you experienced the sound itself.
————————

Finally, when talking about actions you can directly control, の is usually preferred.
→ 酒を飲むのをやめた = "I quit drinking"

Here, the action feels concrete and personally managed rather than abstract.
————————

Quick rule of thumb:

Directly experienced / immediate / personal → の
Abstract / conceptual / informational → こと

Source: part of this video: [www.youtube.com]

From Russian “агитпункт” (agitation point)

Fist rule: When used as a prefix for nouns, if the noun has a Japanese origin (i.e. kun-yomi) or represents tangible day to day things お is used. If it is Chinees in origin (on-yomi) or represents more abstract things, ご is used.

Summary from selftaughtjapanese.com:
The technical rule is that お~ is used for words with the kunyomi, or Japanese reading while ご~ is used for words with the onyomi, or Chinese reading. However, this rule is not always right, so just default to using words with prefixes when you've heard it used that way before.
Read the whole article here:
[selftaughtjapanese.com]

Because in compounds, on'yomi and kun'yomi reading tend to stay together, it's here too. The お reading is (mostly, not always) used for words with an kun'yomi reading, because it's a kun'yomi too. Therefore the ご reading is (mostly) used with on'yomi readings.


Note for the kanji:
Usually written without it, but in many old writings you still see it

Pitch accent: flat.
Some collocations include:
鍬で掘る（ほる）　hoe (up) the soil;
鍬を取る　hoe 《in the fields》; farm;
（処女地などに）（鍬を入れる　cultivate (e.g. virgin soil).
Not to be confused with 桑.
桑

I use a くわ (鍬) to dig up くさ (草)

くわ happens to be the old on’yomi for 禾/カ
Compare 耒. Coincidence?

A lot of food products provide the flavor on the packaging with 味. Ex: いちご味 (Strawberry flavor)

Imagine taking a bite of delicious food and exclaiming, "Ah, gee, this has an amazing taste!"

The phrase "Ah, gee" sounds like "aji," helping you remember that 味 means "taste" or "flavor."

Aji-ed cheese has a distinctive flavour

Many foods improve in *𝗳𝗹𝗮𝘃𝗼𝗿* with "age"「AJI あじ」.
(Also think of the MSG brand 味の素 Aji-no-moto.)

Turkish あじ-var can be used to improve a meal's flavour quite significantly.

Ah, gee, this *tastes* amazing!
(Vega's entry shortened)

You wake up and smell something.
You ask, "Hot toast, eh?"
→ You're guessing!
→ ひょっとして... someone’s cooking!

Related to ひょっと

Do it! Imma-diately! (Now)

I have free time (ひま) right now (いま)

now i will ride my horse (うま) to get there immediately

“Now” means “the current ta-IMA” (time)

To keep the kanji in mind “In my house !” Meaning immediately.

Ima (imma) go now

Xを聞く: Listen to X
Xに聞く: Ask to X

目 (め) で 見る (みる、1)
耳 (みみ) で 聞く、聴く (きく、0)
鼻 (はな) で 嗅ぐ (かぐ、0)
口 (くち) で 話す (はなす、2)
手 (て) で 触る (さわる、0)

聞く is a general purpose verb that means to hear, to listen.
It also has a more specific homophone: 聴く, meaning to listen paying attention (for example to music, to a teacher etc).
However using 聞く is always correct.

The honorific version (尊敬語) of 聞く is お聞きになる.
Note that you conjugate なる. E.g. お聞きになりました.

As with all 尊敬語, it's used to elevate another person's actions, never your own.

Listen or I kicku you!

You listen to the beat of the kick (kiku) drum in a song.

What do you do when someone speak-u? Kiku!

I like to listen to Kikuo! (vocaloid producer)

Sound passes through the gate of the ear (referring to the gate radical of the kanji)

Kanji looks like earbuds (for listening)

きki's hearing is so good that she has to unconjugate herself。

For the Germans: höre wie der Hahn "kiku"reki macht!

In casual speech, だ is often dropped, but だ is not dropped in だよ and だね. (Genki II)

Used in negative sentences (unlike だれでも)

Who’s(だれ) Nemo is this? If the owner doesn’t speak up, I’ll give it to anyone.

No one (negative of anyone) DAREs aNIMOre

How dares Nemo to act like this with everyone? Anyone would get mad because of daring nemo

言う (いう) is the most basic and neutral. It simply means to put something into words. It doesn't require a listener. The focus is on the verbalised words themselves.

これは日本語で何と言いますか？ = "How do you say this in Japanese?"

—————————

話す (はなす) shifts the focus toward communication. It normally assumes some kind of interaction or listener. It's what you use for speaking a language (日本語を話す) and for having a conversation (先生と話した).

少し日本語を話せます = "I can speak a little Japanese."

—————————

しゃべる is basically a casual version of 話す. It means to talk or chat, but it carries a lighter, sometimes slightly negative nuance. You wouldn't use it in formal situations.

彼はよくしゃべる = "He talks a lot" or "He chats a lot" (can be used in a negative sense).

—————————

語る (かたる) feels heavier and more deliberate. It's used when someone recounts something in a structured way—a story, a life experience, a belief system. It often has a literary, emotional, or thematic depth to it.

Both of these mean "I talk to my friend(s) about music", but the one using 語る implies a more deliberate, deeper conversation.

友達と音楽について語る。
友達と音楽について話す。

—————————

述べる (のべる) is formal and often appears in writing, speeches, or official contexts. It's commonly used with things like 意見 or 考え. It means to state or express something in a structured, often objective way.
You wouldn't normally use it in casual conversation with friends; it feels academic/formal.

自分の意見を述べた = "I expressed my opinion." (formal/structured)
自分の意見を言った = "I said my opinion." (casual/spoken)

—————————

Sources: [ja.hinative.com]| [www.youtube.com]| [japanese.stackexchange.com]

言う is sometime pronounced as ゆう instead of いう in casual situation

Frequently paired with particle と for use with quoting/describing: という
There's also a casual slang version of this pair: って

In modern Japanese, 言う is the standard and overwhelmingly dominant spelling, used in everyday writing, speech, media, and formal contexts.

云う, on the other hand, is a non-jōyō (常用漢字) variant that carries a more literary or old-fashioned tone. While some sources suggest a distinction—such as using 言う for one's own speech and 云う for quoting others—in practice this is not a strict or widely followed rule today.

Instead, 云う tends to appear occasionally in fiction or stylized writing where an author wants to evoke a certain nuance.

※ The quoting nuance comes form the meaning of the kanji (云) — 他を引用していう

Sources: [hinative.com] | [japanese.stackexchange.com]

did you hear what they said? ewwWWW!

Are you gonna just let her call IU that??? Say something!

the ambulance said, "iiiiiiiiiiiuuuuu......iiiiiiiiiiiiiuuuuu....".

yes I know ambulances don't speak but this one was in an emergency, so one has to improvise sometimes....

IU - or Lee Ji-eun
(South Korean Actress/Singer)
________________________________

言って - ヨルシカ
Say It - Yorushika

they say/utter/declare lots of things in the EU :)

The 2nd meaning is short for なさい, and is usually mentioned in the flat-tone, in contrast to the 1st meaning/usage which is usually mentioned in a rising-tone.

食べな = Eat up. (from 食べなさい) (such as a command made by a parent)

食べるな = Don’t eat!

"~な" has two seemingly conflicting meanings of "do" and "don't" because ”~な” can be used as a contraction of either (1) "~なさい" (i.e., "do") or (2) "~ない" (i.e., "don't").

To distinguish the two:
(1) ~なさい only attaches to the い-stem of verbs or to the base of an ichidan verb (e.g. これをたべな = "(do) eat this"). So, if you see ~な after a verb's い-stem, it indicates a command to do something (as なさい).
(2) However, ~ない can attach in all other cases, i.e. after the dictionary form of a verb and/or after a complete logical clause (e.g. これをたべるな = "don't eat this"). So, if you see ~な outside a verb's い-stem, it indicates a prohibitive command (as ない).

NAH (な), DON'T do that

If I'm not mistaken, わ is softer than よ

In addition to the regular emphasis usage, It can be used in poetry and songs as "Oh" as in "Oh God" "Farewell, Oh friend". Ex.
時よ, 何を用意しているの? "Oh Time, what do you have in store"
神よ
友よ

Something abstract, not material, like actions and feelings.

abstract thing

verb cannot connect to particle directly, need to put koto to join them together

Generally, 事 (こと)is used to mean thing. When in doubt, if you use こと, you will rarely make a mistake.

事項（じこう) gives the image of each item (事柄). It is close in meaning to 'item.'



事柄（ことがら) is more abstract, relating to the appearance or content. It is close to 事象.



Note that 事項 and 事柄 are not commonly used in everyday conversation; they are used in business and official documents.

[hinative.com]

こと is used for actions, events, or abstract matters, while もの is for things, concepts, or objects that feel more static or concrete.

For example, 愛 (noun) is a concept, so 愛というもの means "this thing called love", while 愛する (verb) is an action, so 愛するということ means "this thing called loving".

Similarly, 生命, life as a concept, takes もの, but 生きる, the act of living, takes こと.
The distinction also appears in phrases like 大切なもの, "important things" (often emotionally valued), versus 大切なこと, "important matters" or "important actions".

An example with people or possessions: 彼のこと refers to abstract things about him or matters concerning him, while 彼のもの means "his thing" or something he owns.

Source: the first few minutes of this video [www.youtube.com]

Both の and こと turn verbs into nouns, but they feel different:
————————

こと is more conceptual and abstract. It treats the action as a general idea and sounds more detached. It's often used for information, ideas, or facts.

の feels more direct and personal. It points to the actual action as it happens. It sounds more immediate, and it's commonly used for things you directly see, hear, feel, or control.
————————

→ 私は死ぬことが怖い = "I'm afraid of death"
Here, the action is treated as a general concept.

→ 私は死ぬのが怖い = "I'm afraid of dying"
This feels more immediate and personal, as if you're afraid of dying rather than death as an abstract idea.
————————

The difference becomes clearer with direct perception. When you directly witness something, you usually use の.

→ 私は子どもが泣いているのを見た = "I saw a child crying"
What you saw wasn't the concept of a child crying—you saw the action itself.

The same contrast appears with hearing, especially when comparing direct perception and reported information.

→ 火山が噴火したことを聞いた = What you heard was the news of the volcano erupting.
Here, you received information about the event.

→ 火山が噴火したのを聞いた = You were there when the volcano erupted. You directly heard it.
In this case, you experienced the sound itself.
————————

Finally, when talking about actions you can directly control, の is usually preferred.
→ 酒を飲むのをやめた = "I quit drinking"

Here, the action feels concrete and personally managed rather than abstract.
————————

Quick rule of thumb:

Directly experienced / immediate / personal → の
Abstract / conceptual / informational → こと

Source: part of this video: [www.youtube.com]

I refuse 断る ことわる to admit we're different 異なる and that's it! This matter 事 こと is now な close.

"oh gee, i have to go to an urgent matter/thing/business about a KOTO instrument. let me grab my COAT of concepts" (idk, imagine raccoons/kids in a trench coat pretending to be a man)

Less formal version of そうですか

(Revised with correction from user itsdomlo)

Unlike other conditionals (e.g. れば、たら), なら is used where there is no doubt in the premise/situation of its attached condition (i.e. where the condition is treated as a given premise). It's used synonymously as "since".

E.g.
えきなら,あそこだ = "If/since it's the station, it's over there."
さくらなら、できる = "If/since it's Sakura, she can do it."
日本に行くなら、おんせんに行ってみる = "If/since you're going to Japan, go and try a hot spring."

In contrast, where the logical conclusion itself is certain, the conditional と is more appropriate.

Source: Cure Dolly Lesson 32

*IF* you go to なら you will see deer

I am no expert, but what I read and understood about なら is contrary to the "How to use" note suggested by the other user.

According to Tofugu:
"なら is attached to the sentence which describes the condition where certain events or situations happen"
Similar descriptions can also be seen in なら

So なら is not really about whether the conclusion is certain or not, it is primarily used when given a condition / context. Meanwhile if the conclusion is certain, と is more appropriate.

Can be used in a negative sense like "Im fine without it" like in the phrase いや、君の嗜好はいい "I don't care about your prefrences / Whatever you like is irrelevant / Im not asking what you like".

This is because you can use いい to dismiss while it still means "good" its more like "what you just said is good (im not talking about that though)".

いいよ / いいですよ can mean "OK / sure / Yeah, sure", but is mainly used to give permission or approval.

E.g. 入ってもいい？ ("May I come in?")
いいよ (You're allowing it)

When someone offers help or a service, replying with いいよ / いいですよ can sound like you're granting permission, rather than naturally accepting.

E.g. 荷物持ちましょうか？ ("Shall I carry your bags?")
いいですよ (can feel a bit off, like "You may, if you want")

In these cases, you'd typically say:
お願いします to accept the offer more naturally.

when something good happens in a tv show you screech in surprise and it sounds like いい!

That’s good EEnough!

いい稲、ね？ (Good rice, huh?)

E IS GOOD LETTER

E is a really good letter, considering it's one of the most used letters in english

It's not "ii" (expression when someone finds something disgusting) but good.

The Roman numeral II is GOOD for expressing the number 2.

“iyi” also means good in Turkish!

Conversational contraction. しているんだ。ー＞　してんだ。

re: sense 3

Confusingly, ん after the negative stem of a verb can be both a contraction of the negative ない / ぬ ending, or of the archaic volitional む ending -- which have completely opposite meanings.

Fortunately the volitional ん verb ending (which is a different dictionary entry, flagged as an archaism) is rather uncommon in modern speech and mostly restricted to specific grammar patterns or intentionally formal/stylistic use of archaic language, so you don't often have to guess whether what looks like a negative is actually a positive.

For the first meaning, ん is most likely not a contraction of いる after the て form but rather a contraction of る.
In the case of ～ている, the contraction is done in two step:
～ている -> ～てる -> ～てん

And that last る -> ん contraction can also be use with verb ending in る like:
する->すん
来る->来ん
It's particularly common when combined with the particle な (the "not" one) for comical effects in casual conversation between friends. As in:
すんな (DON'T do that!)
来んな (DON'T come here!)
One of my favorite example is:
"話しかけてくんな"
Which is quite rude but gives a "Don't you dare come to talk to me!" vibes between friends. That the kind of feeling it can creates (so be careful with that).
Other than that, the ら->ん contraction is also possible as in:
分からない -> 分かんない
Which is relatively common too in casual speech between friends.

I tried to search for some formal explanation but couldn’t find anything that could give me a final answer. Apparently, it could be either some kind of dialect or a general kind of contraction where the entire ラ行 (the ら, れ, る, り, ろ sounds) and な行 (the な, に, ぬ, の, ねsounds) can be replaced with ん. At that point, I gave up because both feel correct and I couldn’t access to more information (nor can I still read research level article… for now). I pretty sure some of those ん contraction are really common mainly because of the kansai dialect combined with manzai comedy for example. But at the same time, I also feel like native used that contraction a bit randomly trough Japanese history. Hence why you have that damn ん which can mean either る、ら、に、の、ぬ、etc. I got traumatized by that ん when I first started to talk with some japanese friends and also when watching youtube. Hope that explanation will help you at least a bit for that (Also now, it’s fun and ん contraction + kansai ben + manzai → best way to make Japaneses laugh)

PS : Just remembered another one but I’m not redoing the entire explanation for that, so I will just leave that here :
やるのか？→ やんのか？ (“wanna fight ?” with a fake yankee vibe kinda, very common between friends)
So, that る → ん contraction can theoretically be applied to any verb with a る ending but in practice, it’s not used everywhere. Like, it’s not common in standard written Japanese, it’s not really “grammatical” either but it’s still extremely common in casual spoken Japanese (especially in those expression). So yeah, don’t know if that explanation is useful or confusing anymore but at least, you will be aware of them if you encounter those expression in the wild x)

Pirates sing Yo, Ho, Ho, but that is rude. We just say HO. Just two sounds.

Pitch accent: ほ＼.

As an adjective, it is often best translated as safe or secure.

安全: security (objective, mostly physical)
安心: safety, peace of mind (subjective, psychological/emotional)

危険 & 危ない: danger, dangerous (objective, mostly physical)
不安: uneasiness, anxiety (subjective, psychological/emotional)

Ancient (anshin) artifacts make me feel safe

Remember it as a combination of the first kanji (& same readings) from あんぜん (safety/security) and しんぱい (concern/worry)

安: women under the roof
心: heart

knowing she's safe inside, my heart feels relief

If I feel safe and secure my heart is relaxed and I have peace of mind.