Quoted from https://sydneytoseoul.wordpress.com V+는지, A+(으)ㄴ지 Proceded by either who, what, why, when, where, whether or how, this ending connects a clause the requires additional information. Corresponds to 'whether or not A/V' in certain cases. Examples 너무 맛있었어요! 어떻게 만들었는지 가르쳐 주세요. It was delicious! Please tell me how you made it. 여자 친구가 있는지 없는지 궁금해요. I wonder whether he has a girlfriend. 청소하는지 쉬는지 잘 모르겠어요. I don't know whether she is cleaning or resting. 내일 날씨가 더운지 알아요? Do you known whether tomorrow's whether will be hot? V+는 것 While you can transform verbs into nouns but using +기, you can also use -는 것. We add it to the verb stem when using present tense. For past tense we use -(으)ㄴ 것, and for future tense use -(으)ㄹ 것. For example, taking the base verb 공부하다: 공부한 것 = what you studied 공부하는 것 = what you study 공부할 것 = what you will study Examples 편지를 받는 것을 좋아해요 I like receiving letters 요즘 일하는 것을 어디예요? Where is it you are working recently? 운동하기는 건강에 좋아요 Exercising is good for your health