Sentence Subject (이 ~가) & Topic (는 ~은)

In this entry we will learn about sentence subject and topic. In order to understand a sentence or to build a sentence we 1st need to understand how to use the subject particle (이 ~가) and topic particle (는 ~은).

Fist we need to keep in mind...
*when it is 1st time a subject is mentioned or when it is a new info
thus we attach 이/가 (-i/-ga) to it.

*When it is an old info or a repeated subject, thus we attach 는/은 (-neun/-eun)
to it.

For example.
A. 이것이 무엇이에요? [igeos-i mueos-ieyo?] {what's this?}
B. 그것은 우산이에요. [geugeos-eun usan-ieyo] {That's an umbrella}

이것[igeos] = the front part 이[i-] means 'this' and the other part
것 [geos/geot] means 'thing'. So when its 그것 [geugeot] it means 'that thing'
since 그[geu-] means 'that'.
무엇 = what.
우산 = umbrella.

You can create topics from any element (except verb) by pulling the element out of
place and saying it first (은~는 attached).

For example
"That student is studying Korean at school now"

A."That student은/는 is studying korean at school now."
-this sentence focus on 'What about that student'. New info is the nature of activity,
not who is doing it.

B."Now은/는 that student is studying Korean at school."
-this sentence is to mention 'what is happening NOW'.

C."At school은/는 that student is now studying korean."
-this sentence is to mention 'whats going on at school'.