How to pronounce 跟不上 in Cantonese (3 out of 4):

但我當初是跟不上
But I didn't follow it at first.

Cantonese Sentence Breakdown

daan6
but
ngo5
I
me
my
us
we
our
self
當初 dong1 co4
originally
si6
is
跟不上 gan1 bat1 soeng5
cannot keep up