Japanese punctuation is easy, but to understand it we need to know a few things.

Most Japanese punctuation was adopted from the West relatively late, so it is not so integral to Japanese as European punctuation is to European languages.

The main functions of periods (。)and commas (、) are directly based on the equivalent European functions and the main difference is that the rules are less clearly established.

Periods are simple enough, since the concept of a sentence is quite straightforward in Japanese – A + B with any modifiers, and any compound of As and Bs that makes a complete logical unit.

Commas are pretty much thrown in whenever someone feels like it (kind of like Internet English). There aren’t definite rules for their use as in (real) English or German. I have heard of Japanese schoolchildren being criticized for overuse of commas* but this is simply a stylistic question and there is no general agreement on comma style. Essentially, if you want to show a natural pause you can use a comma. Concepts like comma-ing off a subordinate clause are not present in Japanese.

The various parentheses are used pretty much as anyone wants to use them too. Some publications or sites will establish their own rules, but there are few general ones.

「 」 are very straightforward. They work like English quotation marks. The only difference I can think of is that in some cases the closing  」can replace a period. Again this is a matter of style. Some publishers do this in their books and some don’t.

『 』 are mostly used for quotes within quotes – rather like single and double quotation marks in English, only the other way around (but English punctuation can be less consistent in this than Japanese punctuation).

〒 is used to mark a postal code in postal addresses and sometimes used as a symbol for (physical) mail in general.

々 is called the 同の字点 (どうのじてん) “same-character mark”. It simply indicates that a kanji is repeated. So words like 木木 (きぎ =trees) or 細細 (こまごま =detailed) are more often written 木々 and 細々.

I have never seen anything like the string of hash to represent foul language. This is probably because foul language is not a thing in Japan the way it is in European languages. That is, there are very few “taboo words” and they are not used in anything like the same manner they are used in European languages. There are of course many ways of being vulgar in Japanese, but the concentration around (and fascination with) a few particular words does not exist.

Some Western otaku types are so attached to Western dirty-word culture that they try to make out that it exists in some form in Japanese but it really doesn’t.

A postscript is called 追伸 (ついしん) and is sometimes used.

Hyphenation is not used in Japanese punctuation because that function really belongs to a word-spaced language – Western languages have separate words (good night) and joined words (goodnight) and sometimes want something between the two (good-night). But this question clearly doesn’t arise in Japanese where the entire concept “word” (as I sometimes try to convey) is actually very different from the western concept – much more fluid and lego-like. (This is why it would not be a good idea to introduce word-spacing into Japanese).

Overall, Japanese punctuation is easier than European punctuation because it is a recent add-on with few rules.

The question-mark is a case in point. Some people wonder when Japanese people insert a ? and the answer is pretty much “when they want to”. It is actually an extremely useful innovation because what it really does is mark intonation.

If we use the か marker in formal speech we don’t need it, but if we want to show that a normal-level sentence uses a rising pitch indicating a question we can pop one in. If it is clear from context we might not bother.

One curious piece of Japanese punctuation that may be puzzling (it puzzled me for a while) is that in books you will sometimes see little marks (rather like Japanese commas or occasionally dots) beside each letter of a word or a group of words in vertical text.

These are either for emphasis or picking out a special use of a word. In practice they work pretty much exactly like italicization in English and were probably based on that and originally introduced for translating Western books. The fact that you can’t type them easily and they seem restricted mainly to books reinforces that idea.

In fact, several things were brought into Japanese during the Meiji Era specifically to facilitate the translation of European novels into Japanese. One example of this is the gendered third-person pronouns 彼 (かれ) and 彼女 (かのじょ), which, believe it or not, did not exist before they were introduced for that purpose.

Note on Japanese punctuation in education

(Purely geeky and about Japanese punctuation in  children’s education. Feel free to ignore)

* I think the criticism of comma-use in schools is not based on an ideal of “correct comma use” the way it is in European languages. I think it centers on the question of using commas as a “crutch” to clarify one’s meaning rather than making oneself clear by the use of precise Japanese.

The underlying thought here, I think, is that since commas are not a part of Japanese structure with a clearly defined usage, while they may be used as stylistic embellishments to indicate pauses etc., the obvious dictum is:

If it isn’t clear without the commas, then it isn’t good Japanese.

But that isn’t something we need to worry about – this is primarily about the way Japanese children learn Japanese.

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