questions about pronunciation of korean consonants
1、ㅅ andㅈ
when pronounced with vowels they both sound like /ts/ in english words. what exactly is their difference?
2、ㄴ
When pronounced alone, it sounds like/n/, but in some words it sounds kinda like /t/, how should i pronounce it?
3、ㄹ
Its pronunciation is like /ʒ/，but in words like 마리 , it's pronounced like /l/，moli，how should i pronounce it exactly?
thx

Question

Answer

1. They are distinguishable when a vowel syllable is attached after it.
For example.
both 빗 and 빚 sound [빋] /bit/ when they are independent or followed by consonant syllable.
With an attached vowel syllable 이, 을, 
빗이 => [비시] , 빗을 => [비슬] , 
빚이 => [비지] , 빚을 => [비즐] ,

2. Please give me the example of /t/ of ㄴ word

3.  ㄹ sound is quite different from  /ʒ/ or Chinese r sound.
Refer to https://www.youtube.com/watch?v=0ZhOeA0RD9o

ㄹ sound is similar to /r/ at initial position of syllable like 라디오, 다리, 사람
ㄹ sound is similar to /l/ at final position of syllable like 물, 불, 이불

마리 is pronounced like /mari/ 
몰리 is pronounced like /moli/

Answer

Based on my limited understanding, it does not seem to be the problems that you mentioned.  For instance,
ᄉ is pronouned as /s/ (s)；ᄌ is pronouned as /t͡ɕ/ (j) [unless there is a sound change when such consonant is located at the word-end (받침)]
ㄴ is pronouned as /n/ (n) [unless there is a nasal-sound change]
ㄹ is pronouned as something between /ɾ ~ l/ (r,l) （there is no such sound like /ʒ/ in KR）

It is suggested to refer to the wikipedia for references.
https://zh.wikipedia.org/wiki/朝鮮語

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