If and when

This chapter will cover the (으)면 and 때 form for creating if and when sentences.

Saying if / when using the (으)면 form

The (으)면 form can be translated to both if and when depending on the sentence. This form is used to mean that something might or might not happen.

It is used for hypothetical situations, so something that might or might not happen.

Building the (으)면 form

Verb Stem + (으)면

1. Get the verb stem.
2. Depending on the ending:
   • If it ends in a consonant: Attach 으면.
   • If it ends in a vowel: Attach 면.
   • If it ends in a ㄹ: Attach 면.
   • For ㅂ-irregular verbs: Remove ㅂ, then attach 우, then 면.
3. Finish the rest of the sentence, or attach 요 if it’s used at the end of a sentence.

Regular ㅂ stems keep ㅂ: 입다 → 입으면.

Examples:

• 먹다 → 먹으면
• 하다 → 하면
• 살다 → 살면
• 맵다 → 매우면

Example sentences using the (으)면 form

추우면 눈이 와요

It snows if/when it's cold.

사전을 사면 얘기해 주세요.

Please tell me if/when you buy a dictionary.

저를 도와주시면 돈을 드릴 수 있어요

I can give you money if you help me.

쿠키를 좋아하면 제가 더 만들어 줄 수 있어요.

If you like the cookies I can make more for you.

You can add 만약에 to emphasize the meaning of if in an (으)면 sentence, making it clear that the situation is hypothetical.

만약에 비가 오면 집에 있을 거예요.

If it rains, I'll stay home.

Saying when using the 때 form

The 때 form talks about the time when something happens, so it can only mean when. It is only used for something that already happened, is happening or will happen.

Building the 때 form

Verb Stem + (을 / ㄹ) 때

1. Get the verb stem.
2. Depending on the ending:
   • If it ends in a consonant: Attach 을 때.
   • If it ends in a vowel: Attach ㄹ 때.
   • If it ends in a ㄹ: Attach 때.
   • For ㅂ-irregular verbs: Remove ㅂ, then attach 우, then ㄹ 때.

Regular ㅂ stems keep ㅂ: 입다 → 입을 때.

Examples:

• 먹다 → 먹을 때
• 하다 → 할 때
• 살다 → 살 때
• 덥다 → 더울 때

For past situations, you can use -았/었을 때, as in 어리다 → 어렸을 때 (when I was young).

Example sentences using the 때 form

심심할 때 영화를 보세요.

Watch a movie when you're bored.

배가 고플 때 이걸 먹어요.

Eat this when you're hungry.

비가 올 때 저는 밖에서 놀 수 없어요.

I can't hang out outside when it rains.

제가 어렸을 때 선생님이 되고 싶었어요.

I wanted to be a teacher (at the time) when I was young.

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Sources & References

• Billy Go’s Beginner Korean Course | #73: If and When