Reading kanjis Kunyomi or onyomi


I know use onyomi and kunyomi for kanjis but i confused for use other means of
kanjis for example 日 this kanji means sun,day Kunyomi:ひ,び,か Onyomi:にち,じつ This
example 昨日 means さくじつ why isn't use にち for kunyomi reading日曜日(にちようび) why is
use び for this word we can use ひor か. I don't understand for Kunyomi or onyomi
reading for kanjies




First of all, you'd most commonly read 昨日 as きのう (a special reading), though
the reading さくじつ is used more formally.

Secondly, you have to bear in mind that the reading of a character is
determined by what surrounds it (i.e. **the word it is being used in** ). You
can't predictably tell which reading will be used in a given word if the kanji
in that word have multiple readings; you just have to remember what they are
for a given word.

naruto's comment on your question contains a great answer.

