Core Pattern Rule: Explaining with -는 거야
This pattern is used to explain, define, or state something as a fact or general truth. It adds a nuance of emphasis or finality, as if you're revealing a key piece of information. It's like saying "The thing is..." or "It's that..." in English.
Formation
It's formed by attaching -는 거야 to an action verb stem. This structure is a combination of:
-는 것: A grammar form that turns a verb clause into a noun phrase (e.g., 하다 → 하는 것 "the act of doing").
이다: The verb "to be."
In conversation, 것 is almost always shortened to 거.
Action Verbs (Present): Verb Stem + -는 거야 (e.g., 하다 → 하는 거야)
Action Verbs (Past): Verb Stem + -(으)ㄴ 거야 (e.g., 했다 → 한 거야)
Descriptive Verbs (Adjectives): Adjective Stem + -(으)ㄴ 거야 (e.g., 예쁘다 → 예쁜 거야)
사랑은 움직이는 거야. / 이건 이렇게 하는 거야. / 실수하면서 배우는 거야.
Native Nuance: Four Key Uses
The -는 거야 pattern is versatile. Here are four common situations where it's used naturally.
Stating a General Truth or Definition
This is for stating principles, life lessons, or definitions with a sense of authority or wisdom.
Context: 원래 인생은 혼자 사는 거야. (Life is meant to be lived alone.)
Explaining a Current Action
When someone seems curious or confused about what you're doing, you use this pattern to explain. It answers an unspoken "Why?" or "What's going on?"
Context: 생각하는 거야. ((In case you were wondering,) I'm thinking.)
Asking for an Explanation
In questions, this pattern is stronger than a simple question. It demands an explanation and can show surprise, frustration, or accusation.
Context: 지금 어딜 가는 거야? (Where do you think you're going now?)
Correcting or Clarifying
It's excellent for making a firm clarification, often using the A가 아니라 B (not A, but B) structure.
Context: 안 하는 게 아니라 못 하는 거야. (It's not that I won't do it, it's that I can't.)