"개가 섬까지 수영합니다."
Translation:The dog swims to the island.
-까지 can be used in sentences to have the meaning of “to/until a place/time.”
-(으)로 means many different things (check the link) but in the cases it translates to "to", I believe it's used to "indicate the direction that something is happening in". So like, "towards" basically.
Well, if I saw a dog swimming to an island, I would be pointing it out as that is not common. Look! The dog is swimming to the island. Now this seems to be something the dog does on a regular basis which is all the more reason for it to be not just any dog. If he does it on a regular basis, then there must be a reason and now the island is probably not just any island either.
In verbs of motion, "towards" implies a direction, but not necessarily a destination, while "to" typically implies destination. For example, if you swim north, you are swimming towards (or toward is slightly more common in American English methinks) the north pole, but you are not swimming to the north pole unless you actually will actually arrive at the north pole.
에 can mean at/in/to.
에서 can mean at, but for something you do at a place that requires going there. Ex: "I work at a school." would be "저는 하교에서 일합니다."
But, 에서 also can mean "from". Ex: "I came from the bank." is "저는 은행에서 왔습니다."
(으)로 can mean both towards and using/by way of. It can be used for any thing; not just locations.
까자 means to the,,, when the sentence says The dog( 개가)when subject's last word is consonants then we use 가 ) swims( this is verb when these words come in sentence then 합니다 join in the verb then is in Korean make object) to the island ( when objects And other words like to the join in each other then we use 섬까지 )
I hope this helps you
If just any dog could do this, then I would put "a", but it is somewhat unusual so I feel like this must be a specific dog. "swims" is a version of the verb used for habitual actions, so if the dog is doing this often then I would think that the dog is going to a specific island.
A dog drinks water. The dog swims to the island.
~까지 means "to" and ~로 has multiple meanings but where it translates to "to" it really means "towards" as it indicates the direction of the verb.