〜（が）気になる

About

「気きになる」 means "to be concerned" or "to be interested in", and the gist of it is that something stimulates your 「気き」 (mind; feelings; heart; etc.).

「気きになる」 commonly uses the が particle to attach to nouns, or nominalized verbs, making ～が気きになる a common pattern.

Some common English approximations of 「気きになる」 are: "to be interested in; to be curious about; to be worried about; to be concerned about".

～(が)気きになる can be used in a myriad of situations, but is most commonly used in casual/polite speech.

E.g. 最近さいきん届とどく、差出人さしだしにんが書かいていない手紙てがみのことが気きになる。 "I'm concerned about the mail I've been getting recently with no sender written on it."

E.g. 好すきな人ひとが私わたしのことをどう思おもっているのか気きになります。 "I'm curious/concerned about how the person I like feels about me."

E.g. マイクが気きになっているのは、その店みせにパイナップルピザがあるかどうかということだ。 "What Mike is concerned with, is whether or not that shop has pineapple pizza."

～気にする is another similar pattern, but generally means that someone is bothered by something:

E.g. あの人ひとの言いっていることを気きにする。 "What that person is saying bothers me."

Compared to ～気きにする, ～気きになる has a wider application of use (isn't necessarily negative), and sounds more like a natural emotional response to something.

Summary

• 

  「気きになる」 means "to be concerned", "to be interested in", or "to be curious about"

• 

  Using the が particle to attach to nouns/nominalized verbs (「～が気きになる」) is common

• 

  ～(が)気きになる is most commonly used in casual/polite speech