Inside - prepositions


So I just learned some new vocabulary, くるま (車) is car but how come ‘inside the car’ is しゃない (車内).
Why do we us the on’yomi reading just because there’s a preposition, and do we use the on’yomi reading when it’s used with a preposition that’s not written in kanji?

Thank you

Nothing to do with a preposition. The on’yomi is used because this is a compound word using two kanji. If there were hiragana attached to make the word, or the kanji by itself, then the Kun’yomi reading would be used. There are exceptions, mostly numbers break rules and compound words in which parts of the body are present break the rules.


Also: that is a single word, not a preposition and a noun. English concepts don’t carry over very well to Japanese!

1 Like

I see, this probably explains why it’s not as weird as I thought. I was just wondering why the hell a word would change from kun’yomi to on’yomi just because there’s a preposition attached to it, but if it isn’t a preposition it’s just like all the other compound words I learned!

While kanji carry meaning, and 車 indeed is a word, the 車 in 車内 is not a word. No reading is changed since “car” and “inside car” do not use the same “car”. Sure, it might be a bit pedantic to point this out, but I really think it’s detrimental to think of kanji as words, because they they aren’t. There is no analogue to kanji in English, which might be why you were tempted to use words as analogues, but that’s what lead you to make the incorrect correlation with prepositions.

1 Like

Yeah maybe “car interior” would be a better translation. Car cabin? It’s in the sense of, “wow, your car interior is so clean”


besides, it would be a postposition (pre = before, post = after)

Yes, I know the 車 in 車内 is not a word on it’s own. I was just thinking too much in my native language when I was thinking about 内 as a preposition (or as a postposition, as dadadavid pointed out)

EDIT: wait, I did think of it as a word on it’s own, otherwise I wouldn’t have asked about it. I guess i’m tired sigh

車の中 would be the “preposition” equivalent of 車内. You can think of 車内 as “car interior” and 車の中 as “inside the car” if it makes it easier.

But the big takeaway is, don’t try to literally translate WK’s meanings such that each part has an English counterpart.