Why is there sometimes a classifier required after "một", but not here?
Yep. In this phrase, "sợi" is the classifier for "dây". "sợi" can also be a noun on its own, which means "string/thread".
Lol. I guessed "How long" at first but the rest of your sentence doesn't make sense to me. ; )
I'm hearing "một sợi giây"... what's the difference between the "d" sound and the "gi" sound in the Northern dialect?
Can anyone answer what this would sound like in southern dialect? I think dây would sound like yai but no idea for sợi...
In Southern dialect:
- sợi -> xợi. <x> as in Vietnamese <x> (xe đạp) or English <s> (sea, sun)
- dây -> /jeɪ/ : /j/ in young, yard and /eɪ/ in May, cake
'Một sợi dây' = 'One strand of string'
'Một' = 'One' 'sợi dây' = 'strand of string' 'dây' = 'string'
this = đây, này; string = dây, sợi, sợi dây.
<d> and <đ> are two different consonants. You may also find these confusing characters later on: a, ă, â, e, ê, o, ô, ơ, u, ư. :)