In a typical written sentence, KANJI carry most of the meaning.
The nouns are written in kanji.
The verb and adjective stems are written in kanji.

Each kanji has two or more "readings". Some have dozens.
Put two or more together and get a compound, a new word that may have some relation to the component parts
(ie, the character for NIHON/Japan).

Some compounds follow a more poetic logic.
Do you remember what you get when you put sun and moon together?

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