“The most common reading for this word has the on’yomi reading for 毎 plus the kun’yomi reading for 月. That makes it まいつき. But it can be read まいげつ using both on’yomi readings too. You can use either!”
But it doesn’t accept まいがつ as a valid reading, so either it does accept “both on’yomi readings” or it doesn’t.
Also why is there change from がつ to げつ in 毎月 but no change from にち to じつ in 毎日? I was under the impression the change to second form happens when we treat both Kanji as a single word, like “monthly” instead of “every month”.
There isn’t a “change”. がつ and げつ are both on’yomi for 月, and one just happens to be a valid reading for the 月 in 毎月 while the other isn’t. Either way, I’d pretend the まいげつ reading doesn’t exist since まいつき is more common.
To add on to @seanblue,
There’s no relation between reading patterns of 日 and 月, they’re entirely unrelated kanji.
The (general) pattern for 月 is if it’s attached to a number, or you’re asking a question in which the expected answer is a number, it’s read がつ (一月・いちがつ、八月・はちがつ、何月・なんがつ). If not, it’s read げつ (今月・こんげつ、来月・らいげつ).
Not really. 日 has an entirely different set of rules, because it’s an entirely different kanji.
一日 in and of itself has a special rule in that it can be read either いちにち as in “one day” or ついたち as “first of a month”. It’s not worth trying to apply the same rules across multiple kanji. They’re just not the same.
A shame, rules like that make it easier to make sense out of it. Though we are speaking about languages where exceptions exist, my own Polish language is plenty guilty of overusing those
If you wanna think about it that way, think of this as Japanese X.0 merged with Chinese at several different points along the way, but instead of updating pronunciations each time they just added new ones.
Well, I’m not sure about other languages but you can see the evolution of English throughout the ages mostly due to people still reading English texts created throughout the ages (Shakespeare plays, etc.) We don’t really have that in Polish, in a sense that, there are single words that fell out of use called archaisms, but overall It didn’t change as much when you read something written in Polish several hundred years ago.
