"The book is not stylish."
In "책이", 이 is more or less a subject marker, right? How do we know when to say "책이" and when to say "책은"?
이/가 = yes, subject markers
책이 지루하다 = The book is boring. 내가 용의자다 = I am the suspect.
은/는 = it depends - sometimes yes, other times no
은/는 is often used to emphasize or compare 2 or more.
‘인생은 짧고 예술은 길다" = Art is long, life is short, "
이 방은 깨끗은 하지만, 너무 좁다. = This room is indeed clean yet too small.
이 방은 깨끗하지만 너무 좁다 = This room is clean but too small.
내 친구는 책은 많다 = My friend has indeed many books. (emphasis is made on books)
내 친구는 책이 많다 = My friend has many books. (No emphasis)
내 아내는 크지만 소심하다 = My wife is big yet timid.
내 아내는 크기는 하지만 소심하다 = My wife is surely big yet timid.
I think '그 책' means that book. ' 이 책' Means this book. '책은' Means 'books are'. Here in the translation '책이' means this book.
이 the determiner is completely different from the subject particle 이/가. When it appears before a noun or noun phrase, 이 is a determiner meaning "this". As a particle appended to the end of a noun, 이/가 marks the sentence subject. Just because two words sound the same doesn't mean they're the same word.
이 책 =this book 그 책= That book 책은= Books are So here 책이 means this book. This app basically goves us the literal word by word translation. Since we are converting it into english to learn the translation comes off as odd as against the fluid usage by a native korean.
The two you put are the same. Did you mean 맛없습니다 and 멋없습니다? 맛없습니다 means "not delicious/tasty" and 멋없습니다 means "not cool/stylish"
The two sounds are allophonic in many English dialects, meaning they don't play a role in distinguishing between words. If you don't hear a difference between ㅏa and ㅓeo, you probably speak a dialect of English where cot and caught are pronounced the same.
ㅏ sounds like the a in father or spa, while ㅓ is somewhere between the aw in crawl and the u in mud.
I'm just curious: could someone give an example or two of dialects that pronounce "cot" and "caught" differently?
This vowel merger is actually relatively new, having cropped up just within the last couple centuries. The Received Pronunciation dialect of UK English still distinguishes the two afaik, and some older recordings of US and Canadian speakers will demonstrate a difference as well. Without the merger, "caught" has a more open, rounder vowel sound than "cot", and tends to be slightly longer as well.