Translation:On my way!
I'm pretty sure kada means to go. During the two years I lived in Seoul, kamnida would have meant I'm going or I go... These should certainly be acceptable responses.
A case might be made that they should be the ONLY acceptable responses. Idiomatic translations are confusing for new learners.
Not 100% on this. I believe in English we say "i'm coming" where as Korean it's "i'm going.. on my way to you"
They may be trying to express this concept.
It's a horrible formal translation, but it's a perfectly reasonable interpretive/material translation. Another would be "coming!"
I think the main acceptable translations should be I am (He/She/It is) going, rather than the idiomatic expression. One thing i would change about this course is to use only literal translations for the main lessons, and utilize the Idiomatic Expressions feature like the Spanish course does if it wants to teach these kinds of translations. I would also force the students to learn how to use words such as I, He, She, etc. so it's not so confusing to translate.For example, instead of saying 갑니다 means I am going, the korean should explicitly state 제가 갑니다 or 얘가/걔가/쟤가/것이 갑니다.
In dramas, they always say it when they're leaving, so I think the translation is right
Both " I'm going" and "on my way" make sense. In many dramas you see for example someone getting an urgent call when he is at home, so he says 갑니다! It can means either I'm going, to notify the others living with him, or on my way to the person waiting for him
I feel like "coming" should be accepted, since we're dealing with colloquialisms.
No, the verb "가다" means, "to go" and here it utilizes the polite ending "-ㅂ니다." The translation is idiomatic in this example, but in general does not imply a subject of the action. Verbs do not conjugate in Korean like they do in Spanish or French, so "갑니다" could just as well mean "he goes" or "they go" depending on the context in which it's found.
Edit: nice ninja edit.
The translation they used is a loose translation, not a literal one. So literally, it means:
But in a colloquial sense, it means:
I'm going! or I go!
And in a loose translation, it can mean "I'm on my way." (I don't like that they used a very loose translation for this)
Also, look at my comment above and you'll see I talk about I/He/She/It etc. :)
In Korean, the subject of a sentence is often omitted. One is supposed to understand the subject via context.
Typically the imperative case would use the -세요 ending, no ending, or the -라 ending, depending on how polite one is being.
On my way as in I am on my way to other places rather than on my way to you
When you add 자 to the verb stem, like 가자, 하자, 먹자, 타자 etc., it adds the meaning "let's"
Though you're right to say "Let's go" is an appropriate translation, it wouldn't be right to say it is more accurate.
자 is a suffix that carries the meaning "let's/let us" You use it by taking the verb stem (drop the 다 from the end of the verb) and adding it to the end.
가자 would mean "Let's go"
같이 공부하자 would mean "Let's study together"
우리가 어릴 때 갔던 공원에 찾고 가자 would mean "Let's find and go to the park that we went to when we were young"