KOREAN

Object Markers (을 / 를)

Attached to the noun being directly acted upon by the verb. 

을: Used when the preceding noun ends in a consonant. 

를: Used when the preceding noun ends in a vowel. 

Subject / Topic Markers (은 / 는)

Attached to the person or thing being talked about (Topic).

은: Used after a consonant ending. 

는: Used after a vowel ending. 

Self-Reference Pronouns ("I")

저 (⁠jeo⁠): Polite / Formal (used with strangers, elders, teachers). 

나 (⁠na⁠): Casual / Informal (used with peers, friends, younger people). 

Verb "To Be" (이다 - is / am / are)

Formal Polite

입니다 (⁠im-ni-da⁠): Used after both vowels and consonants. 

Daily Polite

이에요 (⁠i-e-yo⁠): Used after a consonant ending. 

예요 (⁠ye-yo⁠): Used after a vowel ending. 

Casual / Personal

이야 (⁠i-ya⁠): Used after a consonant ending. 

야 (⁠ya⁠): Used after a vowel ending. 

Korean Counters (수량사)

1) Native Korean Counters

개: General items 

분: People (polite / respectful) 

명: People (standard) 

마리: Animals 

권: Books 

잔: Cups / Glasses 

대: Electronics / Vehicles 

살: Age 

시: Hours (time) 

벌: Clothes 

2) Sino-Korean Counters

년: Years 

월: Months 

일: Days / Dates 

분: Minutes 

초: Seconds 

번: Times / Numbers 

인분: Food servings 

원: Currency / Money

Tens & Large Numbers

30: 삼십 (Sino) / 서른 (Native) 

40: 사십 (Sino) / 마흔 (Native) 

50: 오십 (Sino) / 쉰 (Native) 

60: 육십 (Sino) / 예순 (Native) 

70: 칠십 (Sino) / 일흔 (Native) 

80: 팔십 (Sino) / 여덟 (Native) 

90: 구십 (Sino) / 아흔 (Native) 

100: 백 (⁠baek⁠) 

1,000: 천 (⁠cheon⁠) 

10,000: 만 (⁠man⁠) 

Age Terms (나이)

세: Standard (Sino-Korean) 

살: Standard (Native Korean) 

연세: Honorific / Highly Respectful