Honorific infix (으)시: subject honorification

This grammar is an "infix." That means it lives inside the verb or adjective. It sits right between the stem and the final ending. It is like the filling in a grammar sandwich. You take a verb like 가다 (to go). You find the stem 가. You slide 시 in there. Now you have 가시. Finally, you add your polite ending like 어요. It blends together to become 가세요. It does not change the meaning of the action. It only changes the status of the person doing it. It works with almost any verb or adjective. It is one of the most common sounds you will hear in Korea.

1. 1Creating this form is a simple three-step process.
2. 2First, find the verb or adjective stem by dropping 다.
3. 3Second, look at the bottom of the stem for a consonant (batchim).
4. 4Third, attach the correct version of the infix.
5. 5If the stem ends in a vowel: Add 시.
6. 6Example: 보다 (to see) → 보 + 시 = 보시다.
7. 7If the stem ends in a consonant: Add 으시.
8. 8Example: 앉다 (to sit) → 앉 + 으시 = 앉으시다.
9. 9Special Rule: If the stem ends in ㄹ, drop the ㄹ and add 시.
10. 10Example: 살다 (to live) → 사 + 시 = 사시다.
11. 11When you combine this with the polite ending -어요, 시 + 어요 becomes 셔요 or more commonly 세요. So, 가시다 becomes 가세요.

Use this whenever the subject of your sentence is someone "higher" than you. This includes your parents, grandparents, and teachers. It also includes your boss or older colleagues at work. You should also use it for strangers or customers. Imagine you are in a job interview. You would use (으)시 to ask the interviewer a question. Or imagine you are asking an older person for directions. Using (으)시 shows you have great manners. It makes people want to help you more. It is also used when talking about someone respected who isn't there. If you are telling a friend what your professor said, use (으)시 to show respect to the professor.

There is one golden rule: Never use (으)시 for yourself. Even if you are the King of the world, you don't honor yourself in Korean. It sounds very strange and a bit arrogant. For example, never say 저는 가세요 (I go-honorific). Just say 저는 가요. Also, don't use it for your younger siblings or close friends. Using it with a best friend might make them think you are being sarcastic or weirdly formal. Lastly, don't use it for inanimate objects or animals. Your cat might be the boss of the house, but grammatically, she doesn't get a 시.

One very common mistake is the "Indirect Honorific" trap. People sometimes honor the object instead of the person. You might hear a clerk say 커피가 나오셨어요 (The coffee has come out-honorific). This is technically wrong because you are honoring the coffee! The coffee didn't go to university. It should be 커피 나왔습니다. Another mistake is forgetting irregular verbs. Some verbs change entirely instead of using (으)시. For example, 먹다 (to eat) becomes 드시다, not 먹으시다. 자다 (to sleep) becomes 주무시다. Think of these as the "VIP verbs" that get their own special outfits.

Do not confuse (으)시 with the polite ending -아요/어요. The ending -아요/어요 shows respect to the person listening to you. The infix (으)시 shows respect to the person doing the action. You can use both at the same time! For example: 선생님이 오세요. The 세 (from 시) honors the teacher. The 요 honors the person you are talking to. If you are talking to a friend about a teacher, you might say 선생님이 오셔. Here, you honor the teacher with 시, but you use a casual ending because you are talking to a friend. It is all about who you are talking about versus who you are talking to.