ofcourse Sooyoung but Seohyun is good too.

Sooyoung-
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Seohyun-
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none of them are literaly "fluent"
only fany and sica

Neither of them are fluent

Sooyoung has a better accent

i think Seohyun because she actually tries to read english books

Sooyoung is now featured with Sica and Fany on their interviews, that means something.... and she talks way more than Seohyun on the concerts. not to mention that her accent is better. i saw a video where we couldn't see Sooyoung's face clearly and she was speaking in english and i actually thought it was Tiffany, until someone said it was Sooyoung. but Seohyun is improving

Seohyun

at least the people who voted on Seohyun could explain why

^i did. But its also true that only Tiffany and Jessica are fluent in English everyone seems to able to only speak it.

who knows I have never seen then write or read a book in English