Last week I promised you guys to make a video specifically focusing on the 이/가 particle because it can get quite confusing for Korean learners, considering how it is a unique feature of Korean language that not many other languages have (we definitely don't have these in English).
So this week I decided to discuss the 이/가 particle as a subject marker and compare it with the 는/은 subject marker so that their difference can be clear.
이/가 AS A SUBJECT MARKER
Both 는/은 and 이/가 can be used to denote the subject of the sentence:
고양이는 집 뒤에 있어요- The cat is behind the house
고양이가 집 뒤에 있어요- The cat is behind the house
Technically these two sentences describe the same thing and they both point out to the fact that the cat is the subject of the sentence.. HOWEVER there is a slight difference in the intention of the speaker.
고양이는 will be used when the speaker is intending to compare something e.g.- 고양이는 집 뒤에 있고 개는 집 안에 있어요- The cat is behind the house AND the dog is inside the house.
고양이가, on the other hand, is used in a situation where you simply noticed that the cat is behind the house and decided to mention it. This sentence can stand on it's own and doesn't necessarily call for follow up sentences to start a conversation. This sentence is simply an observation of an instance that the speaker happened to notice.
On that note, here are more examples of sentences where you should use 이/가 particle because they are all random (kind of) observations:
날씨가 좋다!- The weather is nice!
어머 비가 왔다!- Oh my, it's raining!
와, 산이 높다!- Woah, the mountain is high!*
*HOWEVER you can also say 산은 높다 and it will make sense and even mean the same thing as 산이 높다 but, once again, the intent of the speaker will be different.
This brings on the 2nd use for 는/은 particle and that is to talk about general or well-known facts. I mean, everyone knows that generally mountains are high. They wouldn't be called mountains if they weren't, right? That's why we can say 산은 높다 as well as 산이 높다. Some sentences can be random observations and talk about a well-known fact at the same time so it all comes down to what you are trying to say.
Examples of difference between 는/은 and 이/가:
사과는 빨갛다- Generally apples are red (well-known fact).
사과가 빨갛다- An apple that is in front of me and that I just noticed is red
사과는 빨갛다. 바나나는 노랗다.- Generally apples are red, yet bananas are yellow.
사과가 팔갛다- This apple that I just noticed is blue for some reason.
Another use of 이/가:
이/가 puts a greater emphasis on the subject of the sentence. It is used to specify that the subject of the sentence is what the listener should focus their attention on.
내가 밥을 먹었어요 vs. 나는 밥을 먹었어요
Both sentences mean "I ate" or "I ate the food," HOWEVER the first sentence specifies that I ate the food and no one else. However if you're coming home from school and letting your mom know that you've ate and you're not hungry you can just say 나는 밥을 먹었어요, which just means that you're stating a general fact that you have eaten. In this case the important part of the sentence is that you ate and that is what you're trying to convey.
누가 그녀를 좋아해요? - Who likes that girl?
The answer would be: 내가 좋아해요 (or 내가 그녀를 좋아해요)
Here it is easy to see that if the person who asked the question uses the 가 particle (누가) then the answer should also involve that particle (내가). Also, this question focuses on who likes a certain girl so that's why we use 이/가, to put emphasis on that specific aspect of the sentence. This will start making more sense with longer, more complex sentences where the emphasis will make a big difference.
Similarly if someone asks you 너는 누구를 좋아해요?- Who do you like?
You can safely answer 나는 그녀를 좋아해요 because the speaker used the 는 particle in the question (Q: 너는 --> A: 나는).
*Even if the speaker omits the 너는 part and just says 누구를 좋아해요, you can either figure out that you should still use 나는 because the speaker is using 누구 and not 누가, or you can safely omit the 나는 as well and just say 그녀를 좋아해요.
Phewwwww..... hope all this made sense to you guys @__@ I know, particles can get a bit daunting but keep practicing and they will start making sense in no time, I promise!