Translation:The girl is nice.
I keep thinking the "Chak" is "Chaek" and I'm like "The girl is book? what?" but then I realize that its not "Chaek" lol
이 and 가 are the same and mark the subject* of the sentence, while 이 is used if the word on a consonant. Otherwise (for vowels) 가 is used.
을 and 를 mark objects**
은 (vowel) and 는 (consonant) mark a new topic*** and are used instead of the other particles.
- subject = something or someone that does something object = something or someone that something is some to * topic = a new topic in a conversation. in English you could roughly translate "... 는" into "concerning ..." or "about ..."