#1 is the most complicated because you have to account for tense. Basically all it is is changing the verb into a noun-modifying (adjective) form and adding the word "thing" (것) after it. In fact, this is the way the future tense is formed. ㄴ/은 - past tense 는 - present tense ㄹ/을 - future tense 예) 공부하다 공부한 것 - the thing (I) studied 공부하는 것 - the thing (I) study/am studying 공부할 것 - the thing (I) will study When you're just making a general "I like/dislike" statement, you use 는 것. -> 저는 한국어를 공부하는 걸 좋아해요. I like studying Korean. Since "studying Korean" is the object, you add 을 to 것. This can be contracted to 걸. 공부하는 것을 -> 공부하는 걸 -> 저는 책을 쓰는 거하고 티비를 보는 걸 좋아해요. I like writing books and watching TV. 것 -> 거; 것을 -> 걸; 하고/랑 Future tense: -> 내일 저는 한국어를 공부할 거예요. I will study Korean tomorrow. So you're saying "It's studying Korean I will do tomorrow." Sorry this is a bit disorganized >.<If you have any questions let me know. I'm not a native, by the way^^ You can use talktomeinkorean.com and howtostudykorean.com to reinforce, learn more, and practice.

"-ing" can refer to two things basically: 1) the present progressive (to be Ving) or 2) the noun form of verbs (gerund). It seems that you are asking about the latter - converting verbs into nouns. There's some different ways and it could depend on context and the verb. The main ones I can think of are: 1. ㄴ/은/는/ㄹ/을 것 2. 기 3. ㅁ/음 The first two are most common. The third one is used less/in certain situations/mostly with certain words. Examples of the #3 would be "잠", "춤", and "꿈", as in "잠을 자다" (to sleep the sleep), "춤을 추다" (to dance the dance), and "꿈을 꾸다" (to dream the dream). But the kind you yourself would be doing is mostly 1 and also 2. In 2, you remove "다" and add "기". 예) 공부하다 -> 공부하기 ; to study -> studying 요리하다 -> 요리하기 ; to cook -> cooking 수영하다 -> 수영하기 ; to swim -> swimming This is the way you would say "to start Ving/to V". 예) 어제 한국어를 공부하기 시작했어요. (I) started studying Korean yesterday.

One more mix-up of "-ing" you can make if you're just looking at the English letters instead of focusing on meaning: "I am sitting" and "I am standing" and those types of things. They could be present progressive or showing a state. (i.e. "I am in the process of parking my arse down in a seat right now" vs "I have sat down and now I am seated...aka I'm currently left in the state of sitting/being seated"; "I am in the process of lifting my body off of the floor/seat right now" vs "I have already stood up and now I am stood up...aka I'm currently left in the state of standing/being erect/stood up")