는지 (indirect question) - Whether, If

This grammar attaches to verbs, adjectives, or nouns to create an indirect question. You usually pair it with verbs of knowing, asking, or checking. Common partners include 알다 (to know), 모르다 (to not know), and 궁금하다 (to be curious). You might also use it with 확인하다 (to check) or 물어보다 (to ask). It essentially takes a question like "Where is it?" and turns it into "where it is." It functions as a noun clause in the sentence. This means you can add object markers like -(으)ㄹ to it, though people often skip them. It is incredibly versatile and works in past, present, and future tenses. Yes, even native speakers mess this up sometimes, so don't worry! Just remember it is all about that hidden question inside your sentence.

1. 1For Action Verbs in the present tense, simply add -는지 to the stem. For example, 먹다 becomes 먹는지.
2. 2For Descriptive Verbs (Adjectives) in the present tense, use -(으)ㄴ지. If the stem ends in a vowel, use -ㄴ지 like 크다 becoming 큰지. If it ends in a consonant, use -은지 like 작다 becoming 작은지.
3. 3For Nouns, always use 인지. For example, 학생 becomes 학생인지.
4. 4For the Past Tense, use -었/았/였는지 for everything (verbs and adjectives). 갔다 becomes 갔는지 and 예뻤다 becomes 예뻤는지.
5. 5For the Future Tense, use -(으)ㄹ지. 갈 것이다 becomes 갈지.
6. 6Watch out for ㄹ Irregulars. For verbs like 살다, drop the ㄹ and add -는지 to get 사는지.
7. 7For ㅂ Irregulars like 춥다, change it to 추운지.

Use 는지 when you are ordering food and want to ask if it is spicy. You might say, "I want to know if this is spicy." Use it when asking for directions in a new city. "Do you know where the subway station is?" is a classic 는지 sentence. It is also great for job interviews. You can ask, "I am curious what the working hours are." Use it whenever there is a "who, what, where, when, why, or how" involved. It also works for "yes/no" questions. In those cases, we often use the pattern 는지 안 는지 (whether or not). It makes you sound much more sophisticated than just asking direct questions. Think of it like a grammar traffic light; it directs the flow of information smoothly.

Do not use 는지 when you are making a simple "if" condition. If you want to say "If it rains, I will stay home," use -(으)면. 는지 is only for embedded questions. Do not use it when you are 100% certain about a fact and just stating it. For example, "I know that he is a student" usually uses -는 것을 instead of 는지. However, if there is a hint of a question, 인지 works. Also, avoid using it as a sentence ender in formal writing. It usually needs a following verb like 알아요 or 몰라요 to complete the thought. It is not a standalone question mark.

One big mistake is using -는지 for adjectives. Remember, adjectives need -(으)ㄴ지. Saying 좋는지 is wrong; it must be 좋은지. Another common slip-up is the ㄹ irregular. People often say 살는지 instead of the correct 사는지. Don't forget the past tense! Many learners use the present tense even when talking about yesterday. If you are asking if someone *ate*, you must use 먹었는지. Finally, don't confuse this with the time grammar -(으)ㄴ지. That one means "since a certain time" and is used differently. It is like mixing up sugar and salt; they look the same but taste very different!

Let's compare 는지 with -(으)면. -(으)면 is a condition: "If I have money, I'll buy it." 는지 is a question: "I don't know if I have money." See the difference? One is a requirement, the other is an uncertainty. Also, compare it with -는 것. -는 것 describes a known fact or action. 는지 describes an unknown or questioned point. If you say "I know that he eats," use -는 것. If you say "I know what he eats," use 는지. It is a subtle but important distinction that will make your Korean sound much more natural. Think of 는지 as the "mystery" version of -는 것.