Lesson 1: 이다 (to be)

In this first lesson, you’ll learn one of the most essential elements of Korean sentence structure: 이다
We’ll look at how to use it in different speech levels and practice making basic self-introductions. Let’s get started!

1. Meaning

이다 is attached to a noun and is used to describe what someone or something is. It plays a similar role to the English verb “to be” (am, is, are). We use 이다 to say things like:

• I am a student.
• This is a book.
• He is a teacher.

In Korean, instead of using a separate word like "am" or "is", we attach a form of ‘이다’ directly to the noun.
For example:

• 저는 학생입니다. → I am a student.
• 이것은 책이에요. → This is a book.

2. Forms and Usage

이다 is attached to the end of a noun without a space, and the exact form changes depending on:

1) the speech style: Korean has different levels of speech depending on who you're talking to.

• Formal is used in official situations like presentations, interviews, or news broadcasts.
• Informal Polite is used in most daily conversations — with people older than you or in respectful situations.
• Informal Casual is used with friends, younger people, or close family.

2) whether the noun ends in a consonant or a vowel

Style	Ending	Example Sentences
Formal	입니다 is used regardless of final consonant.	저는 선생님입니다. (I am a teacher.)  저는 의사입니다. (I am a doctor.)
Informal Polite	이에요 after a consonant 예요 after a vowel	저는 선생님이에요. (I am a teacher.)  저는 의사예요. (I am a doctor.)
Informal Causual	이야 after a consonant 야 after a vowel	나는 선생님이야. (I’m a teacher.)  나는 의사야. (I’m a doctor.)

Tip: In Korean, both 저 and 나  mean “I”, but they are used differently depending on the level of politeness.
Use 저 when speaking politely or formally. Use 나 when speaking casually or with close friends.

3. More Example Sentences

Korean	English
저는 회사원입니다.	I’m an office worker.
저는 요리사입니다.	I’m cook.
저는 중국 사람이에요.	I am Chinese.
저는 가수예요.	I am a singer.
나는 미국 사람이야.	I’m American.
나는 안나야.	I’m Anna.

4. Practice Exercises

Write or say your self-introduction using formal, informal polite, and informal casual Korean.
Example: Nice to meet you. I’m Sora. I’m a teacher. I’m Korean.
   1) Formal Style: 만나서 반갑습니다. 저는 소라입니다. 선생님입니다. 한국 사람입니다.
   2) Informal Polite Style: 만나서 반가워요. 저는 소라예요. 선생님이에요. 한국 사람이에요.
   3) Informal Casual Style: 만나서 반가워. 나는 소라야. 선생님이야. 한국 사람이야.

TIP: Practice out loud! Try replacing “소라” with your name and “선생님” with your job or role. The more you repeat, the more confident you’ll get with sentence endings.

Great job finishing your first Korean grammar lesson! Now you know how to use 이다 to describe who you are.
Practice introducing yourself using different styles, and don’t worry if you make mistakes. That’s how learning happens!