〜(が)気になる: Things that bother you; Things that interest you

Introduction

Welcome to the most concerning and interesting lesson on MM yet! Today, we talk about...

～(が)気きになる: I'm concerned about (hobbits)

構成こうせい

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  Noun/nominalized verbが気きになる
  Example:
  → マイクのことが気きになる。こんな時間じかんまでどこで何なにしているんだろう。
  "I'm worried about Mike. Where could he be, and what could he be doing until such a (late) time?”

日本語にほんご文法ぶんぽう説明せつめい

• 

  「心配しんぱいに思おもう」、「心こころにひっかかる」、「気きにかかる」という意味いみ。

Overview

Although 気きになる is technically 「気き」 ("spirit; heart; mind; feeling") + 「になる」, this phrase is so commonly used that it has essentially become a verb in and of itself.