Take the sentence: 여자가 동물하고 한국어로 대화합니다
It translates to 'The woman has a conversation with an animal in Korean.'
The connector 하고 is supposed to express that it's connecting 2 words together, right? How do you know what words it is connecting together in this sentence?
Up until this sentence, my understanding was that it would always connect the current word with the next word, though in this sentence it's not clear.
Actually, there is no formal way to determine it. Just the context the sentence is spoken decides.
E.g.
철수가 영수하고 밥을 먹는다.
영수하고 철수가 밥을 먹는다.
철수가 빵하고 밥을 먹는다.
There's no formative difference. (철수 eat (밥 and 빵) / 철수 eat (영수 and 밥)..???? this case is nonsense and sometimes used as jokes.)
Usually when people wants to group two words as a single sentence component, they place them near. Also the two words should match in form.
여자가 동물하고 한국어로 대화합니다.
Case 1. 여자가 (동물하고 한국어)로 대화합니다. 여자 can speak 한국어, but not 동물!
Case 2. (여자가 동물하고) 한국어로 대화합니다.
OK.
Also 하고 is interchangable with 와/과. So if 와/과 form is easier, try thinking after converting 하고 to 와/과.
We have to determine the meaning by context.
Note that 하고 when used immediately after a noun can have three meanings:
(1) The conjugation(활용) of the derived verb or adjective noun + 하다.
This form indicates some sequential order in actions, or connection between two similar ideas. For example:
나는 온라인으로 지원서를 접수하고 인터넷 창을 닫았다.
I submitted the application online and closed the browser window.그는 첫눈에 보기에 순수하고 정직했다.
He looked pure and honest at a first glance.
(2) Connecting or comparing two or more nouns, similar to ~랑. (casual)
This is similar to the conjunction and in English. However sometimes it can also mean or.
서진이하고 정우가 오늘 온대.
≈ 서진이랑 정우가 오늘 온대.
I have heard that Seojin and Jeongwoo is coming today.커피하고 차 중에 뭐가 좋아?
≈ 커피랑 차 중에 뭐가 좋아?
Which do you prefer, coffee or tea?
(3) Indicating the object you did something with. (casual)
나는 신웅이하고 저녁을 먹었다. (casual)
≈ 나는 신웅이와 저녁을 먹었다. (formal)
I had supper with Shinung.
Now we look at the sentence 여자가 동물하고 한국어로 대화합니다.
Obviously (1) doesn't make sense in that there is no such word as 동물하다(to animal).
(2) also doesn't make sense since there we can't have a conversation in 동물.
Hence only (3) makes sense, so we can translate the sentence into "The woman has a conversation with an animal in Korean".
Also note that as written in the comment, often 하고 can be replaced with ~와/과 when used as meanings of (2) or (3). So you can try to substitute it when you want to determine if 하고 is used in those meanings.
Actually when writing formal documents, we have to substitute 하고 with ~와/과, e.g. 서진이랑 정우가 오늘 온대 to 서진이와 정우가 오늘 온다고 합니다.
