A brief explanation of some of the Korean particles. Particles are suffixes that immediately follow nouns or pronouns.
은/는: topic
Marks the topic of the conversation.나는 학생이다.
I am a student.
이것은 연필이다.
This is a pencil.
이/가: subject
Marks the subject of the sentence.내가 마셨다.
I drank.
저것이 한강이야.
This is the Han river.
은/는 vs. 이/가
The subject and the topic particles seem fairly similar. Here are the main things to note:- 은/는 signifies an introduction of a topic
- 은/는 can be used to make a general statement
- 이/가 identifies the subject of the discussion
- 이/가 specifies a particular subject
을/를: object
Specifies the object of the sentence. You can have multiple object markers in a sentence.나는 라면을 먹었다.
I ate ramen.
에: location, time
Used for showing where something is located at, or where someone/something is going to. It is also used for time.그는 가게에 있다.
He is at the store.
마이클은 8월에 왔다.
Michael came in August.
도/또한: additive
Means "also" or "too." 또한 is used when you want to talk about multiple qualities of the same subject.그녀도 공부한다.
She studies too.
정남은 군인이었다. 그는 또한 정치가였다.
Jeong-nam was a soldier. He was also a politician.
Sources include /r/Korean, Wikipedia, and LP's Korean Language Learning blog.