V+(으/이)니

Overview

V+(으/이)니 is a versatile connective ending primarily used in informal contexts to express reason or cause, or to pose an informal, often rhetorical, question about a reason. It often implies a speaker's realization, observation, or a natural consequence stemming from the preceding clause.

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Usage

This ending has two main applications:

1. Expressing Reason or Cause (Discovery/Natural Consequence) When used to express a reason, V+(으/이)니 connects a preceding clause that serves as the cause or basis for the following clause. It often implies that the speaker has discovered or realized something, or that the consequence is a natural outcome of the preceding situation. It's commonly used when the speaker is explaining their observation or a direct result. Example: 비가 오니 (Since it's raining...), 춥니 (Since it's cold...)

2. Asking an Informal Question (Rhetorical/Inquisitive) V+(으/이)니 can also be used to ask an informal, sometimes rhetorical, question about the reason for a situation. It often translates to "Is it because...?" or "Since you're doing X, then...?" The speaker might already have an idea of the reason but is seeking confirmation or expressing a slight surprise or inquiry. This usage is very conversational. Example: 그렇게 피곤하니? (Is it because you're so tired? / Since you're so tired...)

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Conjugation Rules

The conjugation for V+(으/이)니 depends on the final sound of the verb stem:

• If the verb stem ends in a vowel or ㄹ (ri-eul), attach -니.

  • 가다 (to go) -> 가 + 니 -> 가니
  • 만들다 (to make) -> 만드 + 니 -> 만드니

• If the verb stem ends in a consonant (excluding ㄹ), attach -으니.

  • 먹다 (to eat) -> 먹 + 으니 -> 먹으니
  • 읽다 (to read) -> 읽 + 으니 -> 읽으니

• Irregular Verbs: Follow standard irregular verb rules before applying -으니/-니.

  • 듣다 (to listen) -> 들으니
  • 돕다 (to help) -> 도우니

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Knowledge Plus

• Nuance Comparison with -으니까: Both -으니까 and -으니 express reason. However, -으니까 is generally more direct and can be used for commands or suggestions based on the reason. -으니 often implies the speaker's subjective realization or discovery of a reason, or a natural consequence. It tends to be more casual and less assertive than -으니까.
• Nuance Comparison with -아서/어서: -아서/어서 states a simple, objective reason or cause. -으니, on the other hand, often highlights the speaker's personal observation or understanding of why something is happening or what the natural outcome should be.
• Tone: This ending is informal and conversational. Depending on context and intonation, it can sometimes convey a slightly demanding or inquisitive tone, especially in its question form.
• Usage with Nouns: While the prompt specifies V+(으/이)니, the (이)니 form is also used with nouns: Noun + (이)니. If the noun ends in a consonant, attach -이니 (e.g., 학생이니). If the noun ends in a vowel, attach -니 (e.g., 의사이니). This follows the same consonant/vowel distinction as verbs, but for nouns, '이' is explicitly present.