になる (with
な-Adjectives), or
くなる (with
い-Adjectives) is an expression used in Japanese to show that something is ‘becoming (A)’. It can be used with any form of
なる, to highlight that something will become (non-past), is becoming (continuous), or has become (past). It can even be used with negative forms, to show that something ‘will not become (A)’.
The adjective
いい ‘good’ is an exception to the regular conjugation rules for
い-Adjectives, and will conjugate as よくなる, not いくなる.
-
勉強(べんきょう)をしているから、頭(あたま)が良(よ)くなる。
Because I study, I will become smart. (Literally, ‘my head will get good’)