MARKERS
Markers are sort by order of importance.
TOPIC AND SUBJECT MARKERS
In Korean, you'll need to add -는 (topic) or -가 (subject) to a noun that ends with a vowel. It means that you will add -은 (topic) or -이 (subject) to a noun ending with a consonant.
The topic represents what a phrase talks about, but even if the topic and the subject may be the same thing in your language, you should prefer the topic in Korean. Just try to imagine it as an "as far as I'm concerned/referring to me".
Eg: I drink the water → as far as I'm concerned, I drink the water (나는 물을 마셔요).
You'll use the topic markers when you'll need to make a comparison between two things or situations.
Eg: Today I'm in Seoul, yesterday I was in Busan → referring to today, I'm in Seoul, but referring to yesterday, I was in Busan (오늘은 서울에 있어요, 어제는 부산에 있었어요).
REMEMBER THAT in Korean you don't always need to put the subject or the topic, especially if they are understandable from the context.
DON'T ever say 나가 to make 나 into the subject part, say 내가 because it is an exception (same with 너 which means "you" → 네가)!
OBJECT MARKERS
-을 and -를 are the two object markers in Korean.
Basically, you'll need to put -을 after a word that ends with a consonant and so you'll have to put -를 after a word ending with a vowel.
PLACE MARKERS
-에 and -에서 are the most used place markers.
If you want to say you are in a place, you use -에.
Eg: I'm in the library → 도서과에 있어요.
If you want to say you're doing something in a place, you use -에서.
Eg: I'm reading a book in the library → 도서과에서 책을 읽어요.
If you want to say you're going to a place, you use -에.
Eg: I'm going to the restaurant → 식당에 가요.
If you want to say you come from a place, you use -에서.
Eg: Lisa comes from Thailand → 리사는 태국에서 와요.
COMPLEMENT OF THE TERM
In Korean, the complement of the term is attached at the end of the word it refers to and there are two ways to use it.
The first is with the particle -에게, used with people; the second is -한테 and it is only used with animals or objects.
Eg:
아저씨, uncle → 아저씨에게
개, dog → 개한테