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Korean lessons: Lesson 6

Subject marker:   -이/가

As mentioned in Lesson 1, Korean is an agglutinating language.   It means that Korean uses little grammatical devices attached to words to specify their roles in a sentence.  English is not an agglutinating language, employing rather a fixed word order and prepositions in order to specify the role of each part.
A subject of a sentence is the agent (doer) of the action described by the sentence.  Assuming that a state of being can also be treated as an action, a subject can take any kind of predicate, i.e., a verbal, an adjectival, or a nominal predicate.  Think of "S goes," "S is bad," and "S is a man."  In each case, S is the subject.  To mark this subject, Korean attaches either 이 or 가 to it.  -이 is used when the subject word ends without a final consonant (patch'im), whereas -가 is for those ending without a final consonant.
Only nouns can be subjects in Korean, such is the case in English.  In other words, when you see a part of a sentence attached with -이 or -가, you will know that it must be a noun.   However, you might hear sometimes people say sentences without using subject markers -이/가 for subjects.   It is because the sentences were simple and a conversational reality is presumed. For these sentences, subject markers can be replaced by a short pause. In sentences the structure of which is complex, or in written forms, the markers should be specified.

Finally, we get a sentence meaning, "The embassy is far."
Now, let's look at some more examples.